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    60 Products

    Starrett High-Accuracy Combination Squares

    Replace your try square, miter square, depth gauge, height gauge, center-point finder, and level. The blade on these squares meets Fed. Spec. GGG-R-791H, which establishes uniform standards for accuracy, graduations, and size. Blades are labeled with numeric increments that are less than 1" for quick reading.
    Blades with Square Head
    Image of Product. Front orientation. Contains Annotated. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head .
    Image of Product. Inch. Front orientation. ZoomedIn view. Contains Annotated, MultipleImages. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head , Inch.

    Inch

    Square head checks 90° angles.
    Hardened Steel Square Head—Hardened-steel square heads are more durable and last longer than cast iron square heads.
    Satin Blade—Satin blade appearance is corrosion resistant and reduces glare.
    Etched—Etched graduation marks are wear resistant.
    Blade
    Graduation
    Cast Iron
    Square Head
    Hardened Steel
    Square Head
    Blade
    Lg.
    Front Graduations (Numeric
    Graduations)
    Back Graduations (Numeric
    Graduations)
    Lg. Accuracy
    Wd.
    Thk.
    Material
    Appearance
    Color
    Color
    Type
    Head
    Lg.
    Each
    Each
    Inch
    4"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.002" to 0.004"5/8"1/16"SteelSatinChrome, SilverBlackEtched2 1/4"2108A2100000002107A210000000
     
    Replacement Square Head Lockbolts
    Each
    Replacement Lockbolt for Square and Center Heads1955A81000000
    Blades with Square Head and Center Head
    Image of Product. Front orientation. Contains Annotated. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head and Center Head .
    Image of Product. Inch. Front orientation. ZoomedIn view. Contains Annotated, MultipleImages. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head and Center Head , Inch.

    Inch

    Square head checks 90° angles.
    Center head identifies the center on pipes, rods, and shafts.
    Satin Blade—Satin blade appearance is corrosion resistant and reduces glare.
    Etched—Etched graduation marks are wear resistant.
    Blade
    Graduation
    Cast Iron
    Square Head
    Blade
    Lg.
    Front Graduations (Numeric
    Graduations)
    Back Graduations (Numeric
    Graduations)
    Lg. Accuracy
    Wd.
    Thk.
    Material
    Appearance
    Color
    Color
    Type
    Head
    Lg.
    Each
    Inch
    4"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.002" to 0.004"5/8"1/16"SteelSatinChrome, SilverBlackEtched2 1/4"2108A110000000
     
    Replacement Square Head Lockbolts
    Each
    Replacement Lockbolt for Square and Center Heads1955A81000000
    Blades with Square Head with Built-In Level and Scriber
    Image of Product. Front orientation. Contains Annotated. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head with Built-In Level and Scriber.
    Image of Product. Inch/Metric. Front orientation. ZoomedIn view. Contains Annotated, MultipleImages. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head with Built-In Level and Scriber, Inch, Metric, 4/32" Numeric Graduations - 2, 10 mm Numeric Graduations.

    Inch/Metric

    Image of Product. Inch. Front orientation. ZoomedIn view. Contains Annotated, MultipleImages. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head with Built-In Level and Scriber, Inch, 4/32" Numeric Graduations, 8/64" Numeric Graduations - 2.

    Inch

    Square head checks 90° angles.
    Hardened Steel Square Head—Hardened-steel square heads are more durable and last longer than cast iron square heads.
    Satin Blade—Satin blade appearance is corrosion resistant and reduces glare.
    Etched—Etched graduation marks are wear resistant.
    Blade
    Graduation
    Cast Iron
    Square Head
    Hardened Steel
    Square Head
    Blade Lg.
    Front Graduations (Numeric
    Graduations)
    Back Graduations (Numeric
    Graduations)
    Lg. Accuracy
    Wd.
    Thk.
    Material
    Appearance
    Color
    Color
    Type
    Head
    Lg.
    Each
    Head
    Lg.
    Each
    Inch
    6"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.002" to 0.004"3/4"5/64"Steel—SilverBlackEtched2 13/32"2108A440000000————0
    6"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.002" to 0.004"3/4"5/64"SteelSatinChrome, SilverBlackEtched2 13/32"2108A220000002 13/32"2107A220000000
    6"1/32" (4/32"), 1/64" (8/64")1/50" (1/10"), 1/100" (1/10")-0.002" to 0.004"3/4"5/64"SteelSatinChrome, SilverBlackEtched2 13/32"2108A280000002 13/32"2107A28000000
    12"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.0035" to 0.005"1"3/32"Steel—SilverBlackEtched4 1/2"2108A45000000————0
    12"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.0035" to 0.005"1"3/32"SteelSatinChrome, SilverBlackEtched4 1/2"2108A230000003 5/8"2107A23000000
    12"1/32" (4/32"), 1/64" (8/64")1/50" (1/10"), 1/100" (1/10")-0.0035" to 0.005"1"3/32"SteelSatinChrome, SilverBlackEtched4 1/2"2108A290000003 5/8"2107A29000000
    24"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.0035" to 0.007"1"3/32"SteelSatinChrome, SilverBlackEtched4 1/2"2108A250000003 5/8"2107A25000000
    24"1/32" (4/32"), 1/64" (8/64")1/50" (1/10"), 1/100" (1/10")-0.0035" to 0.007"1"3/32"SteelSatinChrome, SilverBlackEtched————03 5/8"2107A32000000
     
    Inch/Metric
    11 3/4"/300 mm0.5 mm (10 mm), 1/32" (4/32")1 mm (10 mm), 1/64" (8/64")-0.0035" to 0.005"/
    -0.09 mm to 0.15 mm    		1"3/32"SteelSatinChrome, SilverBlackEtched4 1/2"2108A260000003 5/8"2107A26000000
     
    Replacements for Squares
    Each
    Replacement Case for Combination Squares with 12" Long Blade4264N110000000
    Replacement Lockbolt for Square and Center Heads1955A8200000
    Replacement Lockbolt for Square, Center, and Protractor Heads1955A830000
    Blades with Square Head with Built-In Level, Center Head, and Scriber
    Image of Product. Front orientation. Contains Annotated. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head with Built-In Level, Center Head, and Scriber.
    Image of Product. Inch. Front orientation. ZoomedIn view. Contains Annotated, MultipleImages. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head with Built-In Level, Center Head, and Scriber, Inch.

    Inch

    Square head checks 90° angles.
    Center head identifies the center on pipes, rods, and shafts.
    Hardened Steel Square Head—Hardened-steel square heads are more durable and last longer than cast iron square heads.
    Satin Blade—Satin blade appearance is corrosion resistant and reduces glare.
    Etched—Etched graduation marks are wear resistant.
    Blade
    Graduation
    Cast Iron
    Square Head
    Hardened Steel
    Square Head
    Blade
    Lg.
    Front Graduations (Numeric
    Graduations)
    Back Graduations (Numeric
    Graduations)
    Lg. Accuracy
    Wd.
    Thk.
    Material
    Appearance
    Color
    Color
    Type
    Head
    Lg.
    Each
    Head
    Lg.
    Each
    Inch
    6"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.002" to 0.004"3/4"5/64"SteelSatinChrome, SilverBlackEtched————02 13/32"2107A120000000
    12"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.0035" to 0.005"1"3/32"SteelSatinChrome, SilverBlackEtched4 1/2"2108A1300000003 5/8"2107A13000000
     
    Replacements for Squares
    Each
    Replacement Case for Combination Squares with 12" Long Blade4264N110000000
    Replacement Lockbolt for Center Heads1955A8500000
    Replacement Lockbolt for Square and Center Heads1955A8200000
    Replacement Lockbolt for Square, Center, and Protractor Heads1955A830000
    Blades with Square Head with Built-In Level, Center Head, Protractor Head, and Scriber
    Image of Product. Front orientation. Contains Annotated. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head with Built-In Level, Center Head, Protractor Head, and Scriber.
    Image of Product. Inch. Front orientation. ZoomedIn view. Contains Annotated, MultipleImages. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head with Built-In Level, Center Head, Protractor Head, and Scriber, Inch.

    Inch

    Square head checks 90° angles.
    Protractor head measures angles.
    Center head identifies the center on pipes, rods, and shafts.
    Etched—Etched graduation marks are wear resistant.
    Blade
    Graduation
    Cast Iron
    Square Head
    Blade
    Lg.
    Front Graduations (Numeric
    Graduations)
    Back Graduations (Numeric
    Graduations)
    Lg. Accuracy
    Wd.
    Thk.
    Material
    Color
    Color
    Type
    Head
    Lg.
    Each
    Inch
    12"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.0035" to 0.005"1"3/32"SteelSilverBlackEtched4 1/2"2108A570000000
    24"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.0035" to 0.007"1"3/32"SteelSilverBlackEtched4 1/2"2108A59000000
     
    Replacements for Squares
    Each
    Replacement Case for Combination Squares with 12" Long Blade4264N110000000
    Replacement Lockbolt for Square, Center, and Protractor Heads1955A830000
    Blades with Square Head with Built-In Level, Center Head, Reversible Protractor Head, and Scriber
    Image of Product. Front orientation. Contains Annotated. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head with Built-In Level, Center Head, Reversible Protractor Head, and Scriber.
    Image of Product. Inch/Metric. Front orientation. ZoomedIn view. Contains Annotated, MultipleImages. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head with Built-In Level, Center Head, Reversible Protractor Head, and Scriber, Inch, Metric, 4/32" Numeric Graduations - 2, 10 mm Numeric Graduations.

    Inch/Metric

    Image of Product. Inch. Front orientation. ZoomedIn view. Contains Annotated, MultipleImages. Squares. Starrett High-Accuracy Combination Squares, Blades with Square Head with Built-In Level, Center Head, Reversible Protractor Head, and Scriber, Inch, 4/32" Numeric Graduations, 8/64" Numeric Graduations - 2.

    Inch

    Square head checks 90° angles.
    Protractor head measures angles.
    Center head identifies the center on pipes, rods, and shafts.
    Hardened Steel Square Head—Hardened-steel square heads are more durable and last longer than cast iron square heads.
    Satin Blade—Satin blade appearance is corrosion resistant and reduces glare.
    Etched—Etched graduation marks are wear resistant.
    Blade
    Graduation
    Cast Iron
    Square Head
    Hardened Steel
    Square Head
    Blade Lg.
    Front Graduations (Numeric
    Graduations)
    Back Graduations (Numeric
    Graduations)
    Lg. Accuracy
    Wd.
    Thk.
    Material
    Appearance
    Color
    Color
    Type
    Head
    Lg.
    Each
    Head
    Lg.
    Each
    Inch
    12"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.0035" to 0.005"1"3/32"Steel—SilverBlackEtched4 1/2"2108A510000000————0
    12"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.0035" to 0.005"1"3/32"SteelSatinChrome, SilverBlackEtched————03 5/8"2107A510000000
    12"1/32" (4/32"), 1/64" (8/64")1/50" (1/10"), 1/100" (1/10")-0.0035" to 0.005"1"3/32"Steel—SilverBlackEtched4 1/2"2108A54000000————0
    12"1/32" (4/32"), 1/64" (8/64")1/50" (1/10"), 1/100" (1/10")-0.0035" to 0.005"1"3/32"SteelSatinChrome, SilverBlackEtched————03 5/8"2107A54000000
    24"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.0035" to 0.007"1"3/32"Steel—SilverBlackEtched4 1/2"2108A53000000————0
    24"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.0035" to 0.007"1"3/32"SteelSatinChrome, SilverBlackEtched————03 5/8"2107A53000000
    24"1/32" (4/32"), 1/64" (8/64")1/50" (1/10"), 1/100" (1/10")-0.0035" to 0.007"1"3/32"SteelSatinChrome, SilverBlackEtched————03 5/8"2107A56000000
     
    Inch/Metric
    11 3/4"/300 mm0.5 mm (10 mm), 1/32" (4/32")1 mm (10 mm), 1/64" (8/64")-0.0035" to 0.005"/
    -0.09 mm to 0.15 mm    		1"3/32"Steel—SilverBlackEtched4 1/2"2108A55000000————0
    11 3/4"/300 mm0.5 mm (10 mm), 1/32" (4/32")1 mm (10 mm), 1/64" (8/64")-0.0035" to 0.005"/
    -0.09 mm to 0.15 mm    		1"3/32"SteelSatinChrome, SilverBlackEtched————03 5/8"2107A57000000
     
    Replacements for Squares
    Each
    Replacement Case for Combination Squares with 12" Long Blade4264N110000000
    Replacement Lockbolt for Square, Center, and Protractor Heads1955A830000

    Starrett High-Accuracy Combination Square Blades

    Image of Product. Inch. Front orientation. ZoomedIn view. Contains Annotated, MultipleImages. Combination Square Blades. Starrett High-Accuracy Combination Square Blades, 4/32" Numeric Graduations.
    Image of Product. Inch/Metric. Front orientation. ZoomedIn view. Contains Annotated, MultipleImages. Combination Square Blades. Starrett High-Accuracy Combination Square Blades, 10 mm Numeric Graduations.

    Inch

    Inch/Metric

    Use these blades with Starrett High-Accuracy Combination Square Heads. They meet Fed. Spec. GGG-R-791, which establishes uniform standards for accuracy, graduations, and size. Blades are labeled with numeric increments that are less than 1" for quick reading. All have a corrosion-resistant satin chrome-plated finish that reduces glare and wear-resistant etched markings.
    Graduation
    Lg.
    Front Graduations (Numeric
    Graduations)
    Back Graduations (Numeric
    Graduations)
    Lg. Accuracy
    Wd.
    Thk.
    Color
    Color
    Type
    Each
    Inch
     
    Satin Chrome-Plated Steel
    4"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.002" to 0.004"5/8"1/16"SilverBlackEtched1955A32000000
    6"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.002" to 0.004"3/4"5/64"SilverBlackEtched1955A3400000
    6"1/32" (4/32"), 1/64" (8/64")1/50" (1/10"), 1/100" (1/10")-0.002" to 0.004"3/4"5/64"SilverBlackEtched1955A3500000
    12"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.0035" to 0.005"1"3/32"SilverBlackEtched1955A3600000
    12"1/32" (4/32"), 1/64" (8/64")1/50" (1/10"), 1/100" (1/10")-0.0035" to 0.005"1"3/32"SilverBlackEtched1955A37000000
    24"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.0035" to 0.007"1"3/32"SilverBlackEtched1955A41000000
    24"1/32" (4/32"), 1/64" (8/64")1/50" (1/10"), 1/100" (1/10")-0.0035" to 0.007"1"3/32"SilverBlackEtched1955A42000000
    36"1/32" (4/32"), 1/64" (8/64")1/8" (1"), 1/16" (1")-0.0035" to 0.007"1"3/32"SilverBlackEtched1955A51000000
     
    Inch/Metric
     
    Satin Chrome-Plated Steel
    11 3/4"/300 mm0.5 mm (10 mm), 1/32" (4/32")1 mm (10 mm), 1/64" (8/64")-0.0035" to 0.005"/-0.09 mm to 0.15 mm1"3/32"SilverBlackEtched1955A44000000
     

    Starrett High-Accuracy Combination Square Heads

    Attach to Starrett High-Accuracy Combination Square Blades with the included lockbolts.
    Square Heads
    Image of Product. Front orientation. Combination Square Heads. Starrett High-Accuracy Combination Square Heads, Square Heads.
    Square heads check 90° angles.
    Cast Iron—Cast iron heads are durable, so they resist dents and scratches. However, they corrode more easily than zinc alloy heads.
    Hardened Steel—Hardened steel heads are more durable and last longer than cast iron heads.
    Cast Iron
    Hardened Steel
    For Blade
    Lg.
    Features
    Each
    Each
    4"—1955A110000001955A14000000
    6"Built-In Level1955A12000001955A15000000
    12" to 48"Built-In Level1955A13000001955A16000000
    Replacement Square Head Lockbolts
    Image of Product. Front orientation. Square Head Lockbolts. Starrett High-Accuracy Combination Square Heads.
    For Head Style
    For Blade Lg.
    Each
    Center, Square4"1955A81000000
    Center, Square6"1955A8200000
    Center, Square, Protractor12" to 36"/300 mm to 600 mm1955A830000
    Center Heads
    Image of Product. Front orientation. Combination Square Heads. Starrett High-Accuracy Combination Square Heads, Center Heads.
    Center heads identify the center on pipes, rods, and shafts.
    Cast Iron—Cast iron heads are durable, so they resist dents and scratches. However, they corrode more easily than zinc alloy heads.
    Hardened Steel—Hardened steel heads are more durable and last longer than cast iron heads.
    Cast Iron
    Hardened Steel
    For Blade
    Lg.
    Each
    Each
    4"1955A170000001955A21000000
    6"1955A18000001955A22000000
    12" to 48"1955A19000001955A23000000
    Replacement Square Head Lockbolts
    Image of Product. Front orientation. Square Head Lockbolts. Starrett High-Accuracy Combination Square Heads.
    For Head Style
    For Blade Lg.
    Each
    Center, Square4"1955A81000000
    Center, Square6"1955A8200000
    Center6"1955A8500000
    Center, Square, Protractor12" to 36"/300 mm to 600 mm1955A830000
    Protractor Heads
    Image of Product. Front orientation. Combination Square Heads. Starrett High-Accuracy Combination Square Heads, Protractor Heads.
    Protractor heads measure angles.
    Cast Iron—Cast iron heads are durable, so they resist dents and scratches. However, they corrode more easily than zinc alloy heads.
    Protractor
    Cast Iron
    For Blade
    Lg.
    Reversible
    Features
    Angle Measured
    Range
    Graduations (Numeric
    Increments)
    Each
    12" to 48"NoBuilt-In Level0° to 180°1° (10°)1955A290000000
    12" to 48"YesBuilt-In Level0° to 180°1° (10°)1955A25000000
    Replacement Square Head Lockbolts
    Image of Product. Front orientation. Square Head Lockbolts. Starrett High-Accuracy Combination Square Heads.
    For Head Style
    For Blade Lg.
    Each
    Center, Square, Protractor12" to 36"/300 mm to 600 mm1955A8300000
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