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    26 Products

    Granite Inspection Parallels

    Image of Product. Front orientation. Inspection Parallels. Granite Inspection Parallels.
    Support and align workpieces for precise measuring and inspecting. Made of black granite, these inspection parallels won’t rust or warp from temperature changes, and they won’t scratch surfaces. Unlike metal inspection parallels, they’re also nonmagnetic, so they won’t interfere with sensitive electronic equipment. Made in pairs, these inspection parallels are precision ground to tight tolerances for matching flat surfaces on two or four sides. They come with a certificate traceable to NIST confirming their accuracy.
    2 Precision-Ground Sides—Inspection parallels with 2 precision-ground sides have a tight parallel tolerance on the top and bottom edges.
    4 Precision-Ground Sides—Inspection parallels with 4 precision-ground sides have a tight parallel tolerance on the top edge, bottom edge, and both faces.
    Inspection-Grade A Plate—Inspection Grade A inspection parallels are used for general inspections and quality-control work. They’re slightly less precise than Grade AA ones.
    Laboratory-Grade AA Plate—Laboratory Grade AA inspection parallels have the tightest tolerance for the highest level of accuracy. They’re best for inspections and quality-control work in calibration labs.
    Inspection-Grade A Plate
    Laboratory-Grade AA Plate
    Lg.
    Thk.
    Ht.
    Material
    Certificate Type
    Parallel
    Tolerance
    Pair
    Parallel
    Tolerance
    Pair
    Sold as Matched Pair
     
    2 Precision-Ground Sides
    6"3/4"1"Black GraniteAccuracy Certificate Traceable to NIST0.0001"7296N1300000000.00005"7296N110000000
    12"1"2"Black GraniteAccuracy Certificate Traceable to NIST0.0001"7296N140000000.00005"7296N12000000
     
    4 Precision-Ground Sides
    6"3/4"1"Black GraniteAccuracy Certificate Traceable to NIST0.0001"7296N170000000.00005"7296N15000000
    12"1"2"Black GraniteAccuracy Certificate Traceable to NIST0.0001"7296N180000000.00005"7296N16000000
     

    Surface Plates

    Image of Product. Front orientation. Surface Plates. Rectangular Plate.

    Rectangular Plate

    With flatness tolerances thinner than a strand of hair, these plates give you the flattest possible surface for accurate measurements. They’re typically used as a reference plane to inspect finished products and calibrate precision measuring tools, such as height gauges and dial indicators. Unlike metal plates, these granite plates won’t rust or interfere with nearby electronics. They also won’t warp when temperatures fluctuate. To maintain their flatness and finish, rotate plates regularly and apply granite cleaner (not included) to remove particles without leaving a residue.
    Also Available: Other plate sizes. Please order 2245A999 and specify grade, length, width, thickness, and with or without ledges.
    Laboratory-Grade AA Plate—Best for precision inspections and quality-control work in calibration labs. These plates have the tightest flatness tolerance for the highest level of accuracy.
    Inspection-Grade A Plate—Your go-to for general inspections and quality-control work. These plates are slightly less precise than grade AA plates with double the flatness tolerance.
    Red—Resist wear better than black plates to last up to five times longer. With a higher percentage of quartz, you can slide parts across these plates without worrying about nicks and scratches.
    Surface Plate Covers—Prevent dust and debris from accumulating on plates when you’re not using them.
    Plates
    Surface
    Plate Covers
    Rectangular Plate
    Flatness
    Tolerance
    Lg.
    Wd.
    Ht.
    Color
    Specs. Met
    Certificate Type
    Wt.,
    lb.
    Each
    Each
    Laboratory-Grade AA Plate
     
    Granite
    0.00005"18"12"4"RedASME B89.3.7, Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST842245A10500000000022455A64000000
    0.000075"24"18"4"RedASME B89.3.7, Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST1682245A1060000000022455A65000000
     
    Inspection-Grade A Plate
     
    Granite
    0.0001"12"8"2"RedASME B89.3.7, Fed. Spec. GGG-P-463Accuracy Certificate Traceable to NIST202245A10400000022455A101000000
     
    Surface Plate Stands

    Digital Precision Levels

    Image of Product. Front orientation. Levels. Digital Precision Levels.
    You won’t need to choose between precision or convenience with these levels. Their highly sensitive sensor accurately determines level, even when placed on vibrating machinery and equipment. Clearly read the high-contrast display in any lighting conditions – no need to squint to read vials. They stabilize in five seconds after you position them, so you can quickly check the alignment of one part and move on to the next item. You can also view the angle and slope of a surface without a separate tool. When you need to use these levels under machines or in tight spaces between parts, connect them to your smart device via Bluetooth. The free app lets multiple users view readings remotely.
    In addition, the V-shaped indentation on the base means you can rest them on flat and curved surfaces alike. These levels also have a false zero setting lets you set any position as a reference point when you need to replicate angles on multiple surfaces.
    Granite Base—Granite chips off instead of denting or deforming when dropped. It also won’t corrode in wet environments like cast iron or steel, so the base always stays accurate.
    Housing
    Batteries
    Lg.
    Wd.
    Ht.
    Sensitivity
    Material
    Color
    Base
    Material
    Container
    Type
    Included
    No.
    Req.
    Data Connection
    Each
    4 15/16"1 9/16"2 1/4"0.017"/1 ft., 4 min/0.1"PlasticBlackGraniteCarrying CaseYes1Bluetooth, USB-C6700N110000000
    7 7/8"1 9/16"2 1/4"0.017"/1 ft., 4 min/0.1"PlasticBlackGraniteCarrying CaseYes1Bluetooth, USB-C6700N12000000
     

    Two-Axis Precision Levels

    Image of Product. Front orientation. Levels. Two-Axis Precision Levels, Straight.

    Straight

    Level horizontal surfaces in two directions at the same time with the highest degree of accuracy. The highly sensitive glass vials on these levels sit perpendicular to one another – place them on the corner of platforms and surface plates to check if they’re tilting sideways, forwards, or backwards.
    Granite Base—Granite chips off instead of denting or deforming when dropped. It also won’t corrode in wet environments like cast iron or steel, so the base always stays accurate.
    No. of
    Vials
    Housing
    Levels
    Lg.
    Wd.
    Ht.
    Sensitivity
    Horizontal
    Cross
    Check
    Vial
    Material
    Material
    Color
    Base
    Material
    Each
    Straight
    4 15/16"1 9/16"2 3/8"0.0002"/1 ft., 0 min/0.1"11GlassPlasticBlackGranite5833N110000000
    4 15/16"1 9/16"2 3/8"0.0006"/1 ft., 0 min/0.1"11GlassPlasticBlackGranite5833N13000000
    4 15/16"1 9/16"2 3/8"0.001"/1 ft., 0 min/0.1"11GlassPlasticBlackGranite5833N15000000
    7 7/8"1 9/16"2 3/8"0.0002"/1 ft., 0 min/0.1"11GlassPlasticBlackGranite5833N12000000
    7 7/8"1 9/16"2 3/8"0.0006"/1 ft., 0 min/0.1"11GlassPlasticBlackGranite5833N14000000
    7 7/8"1 9/16"2 3/8"0.001"/1 ft., 0 min/0.1"11GlassPlasticBlackGranite5833N16000000
     
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