M27 Couplings | McMaster-Carr

With the strength to handle extreme pressures, these fittings can be used to connect equipment in hydraulic fluid lines. 316 stainless steel fittings have excellent corrosion resistance. BSPP and metric male threads have either a gasket or a gasket and washer to prevent leaks. UN/UNF (SAE) threads are also known as O-ring boss threads; the male threads have a gasket to prevent leaks.

For technical drawings and 3-D models, click on a part number.

Straight Adapters, Female × Male

BSPP, Metric, and
UN/UNF (SAE)
Male Threads with Gasket

For Use With: See table
Specifications Met: See table

						316 Stainless Steel
Thread Size (A)	Dash Size (A)	Thread Size (B)	Dash Size (B)	Max. Pressure	For Use With		Each
UN/UNF (SAE) Female × Metric Male
1 1/16"-12	12	M27 × 2 mm	__	3,500 psi @ 72° F	Hydraulic Fluid (Petroleum Base), Oil, Water	000000000	000000
Metric Female × UN/UNF (SAE) Male
M27 × 2 mm	__	1 1/16"-12	12	5,000 psi @ 72° F	Hydraulic Fluid (Petroleum Base), Oil, Water	000000000	00000

Straight Adapters, Male

Front

BSPP and Metric
Male Threads with
Gasket and Washer

For Use With: See table
Specifications Met: See table

						316 Stainless Steel
Pipe Size (A)	Dash Size (A)	Thread Size (B)	Max. Pressure	For Use With	Specifications Met		Each
BSPP Male × Metric Male
3/4	12	M27 × 1.5 mm	3,600 psi @ 72° F	Hydraulic Fluid, Oil, Water	DIN 7631, ISO 1179, ISO 8434-6, ISO 9974	00000000	000000

Replacement Washers

Temperature Range: -22° to 230° F

		316 Stainless Steel
For Pipe Size	Gasket Material		Each
For BSPP Male
3/4	Buna-N Rubber	00000000	00000

Compact Extreme-Pressure Steel Threaded Pipe Fittings

These fittings are strong enough to handle extreme pressures, yet small enough to fit into cramped spaces. They are galvanized steel, which has fair corrosion resistance. BSPP and metric male threads have a gasket and washer to prevent leaks.

For technical drawings and 3-D models, click on a part number.

Straight Adapters, Female × Male

BSPP and Metric
Male Threads with
Gasket and Washer

For Use With: See table
Specifications Met: See table

NPT Female × Metric Male
Pipe Size (A)	Dash Size (A)	Thread Size (B)	Max. Pressure	For Use With	Specifications Met		Each
3/4	12	M27 × 2 mm	3,500 psi @ 72° F	Air, Hydraulic Fluid, Oil, Water	ASME B1.20.3, DIN 7631, ISO 6149, ISO 9974	00000000	000000

Replacement Washers

Temperature Range: -20° to 230° F

For Metric Male
For Thread Size	Gasket Material		Each
M27	Buna-N Rubber	00000000	00000

High-Pressure Brass Threaded Pipe Fittings

These fittings have the strength to handle high-pressure applications. They are brass for good corrosion resistance.

NPTF (Dryseal) threads are compatible with NPT threads.

For technical drawings and 3-D models, click on a part number.

Straight Adapters with Gasket, Female × Male

Front

Metric Male Threads
with
Gasket

For Use With: Air, Water, Natural Gas, Oil
Specifications Met: SAE J530, SAE J531

NPTF Female × Metric Male
Pipe Size	Thread Size	Max. Pressure	Male End Gasket Material		Each
1/2	M27 × 2 mm	1,000 psi @ 72° F	Fluorocarbon Rubber	000000000	000000

Supported 45° Flared Fittings for Copper and Brass Tubing

For Use With: Air, Cutting Oil, Diesel Fuel, Fuel Oil, Mineral Oil, Refrigerant, Water
Temperature Range: -65° to 250° F
Tubing: Use with seamless brass and copper
Specifications Met:
Metric: SAE J512, SAE J513, UL Listed
All other fittings: SAE J512, UL Listed; except tee connectors for 1/2" tube OD

The flared end nests inside the fitting body, providing extra support to the tubing. Fittings are also known as inverted 45° flared fittings, refrigeration fittings, and SAE fittings. To assemble, place the nut (sold separately) on the tubing, flare the end of the tubing, then insert the tubing into the fitting and tighten the nut. Fittings are brass for good corrosion resistance.

For technical drawings and 3-D models, click on a part number.

Straight Adapters, Tube × Male Threaded Pipe

Metric

For Tube
OD	Wall Thick.	Thread Size	Thread Pitch, mm	Material	Max. Pressure		Each
Metric Threads
5/8"	0.035"	M27	2	360 Brass	650 psi @ 72° F	00000000	000000
3/4"	0.035"	M27	2	360 Brass	550 psi @ 72° F	00000000	00000

37° Flared Fittings for Steel Tubing

Tubing: Use with seamless steel
Specifications Met: SAE J514

Also known as JIC (Joint Industrial Council) fittings, these provide a tight metal-to-metal seal on tubing that is flared to 37°. They require a nut and a sleeve (ferrule) for each tube end. Nuts and sleeves are sold separately. Fittings are zinc-plated steel for fair corrosion resistance.

To prevent leaks, UN/UNF (SAE) male threads have a gasket. Metric and BSPP male threads have either a gasket or a gasket and washer.

For technical drawings and 3-D models, click on a part number.

Straight Adapters, Male Tube × Male Threaded Pipe

For Use With: See Table
Temperature Range: See Table

Metric Threads
For Tube OD	Thread Size	Thread Pitch, mm	For Use With	O-Ring Material	Material	Gasket Material	Max. Pressure	Temp. Range, °F		Each
3/4"	M27	2	Air, Fuel Oil, Hydraulic Fluid, Mineral Oil	Buna-N Rubber	Zinc-Plated Steel	Buna-N Rubber	1,400 psi @ 72° F	-30° to 200°	00000000	0000000

90° Elbow Adapters, Male Tube × Male Threaded Pipe

For Use With: NPTF, Metric, BSPP with O-Rings, BSPT: Air, Fuel, Oil, Hydraulic Fluid, Mineral Oil
BSPP with Washers: Cutting Oil, Fuel Oil, Hydraulic Fluid, Mineral Oil
Temperature Range: NPTF and BSPT: -60° to 400° F
Metric and BSPP with O-Rings: -30° to 200°F
BSPP with Washers: -20° to 212° F

Metric Threads
For Tube OD	Thread Size	Thread Pitch, mm	O-Ring Material	Material	Gasket Material	Max. Pressure		Each
3/4"	M27	2	Buna-N Rubber	Zinc-Plated Steel	Buna-N Rubber	1,400 psi @ 72° F	00000000	0000000

Nuts

For Use With: Air, Fuel Oil, Hydraulic Fluid, Mineral Oil
Temperature Range: -60° to 400° F

For Tube OD	Nut Material	Max. Pressure		Each
3/4"	Zinc-Plated Steel	3,000 psi @ 72° F	000000000	00000

Sleeves

For Use With: Air, Fuel Oil, Hydraulic Fluid, Mineral Oil
Temperature Range: -60° to 400° F

Use these sleeves with a nut and fitting to provide a tight metal-to-metal seal on steel tubing that is flared to 37°. Sleeves are zinc-plated steel for fair corrosion resistance. They are also known as ferrules.

Sleeves for metric tube ODs convert the fitting from inch to metric.

For Tube OD
Inch	Metric, mm	Sleeve Material	Max. Pressure		Each
Inch
3/4"	__	Zinc-Plated Steel	3,000 psi @ 72° F	000000000	00000
Metric
3/4"	18	Zinc-Plated Steel	3,000 psi @ 72° F	000000000	0000

Metric Medium-Strength Steel Coupling Nuts—Class 8

Often referred to as extension nuts, use these to connect and extend threaded rods. They're comparable in strength to Class 8.8 bolts.

Zinc-plated steel coupling nuts resist corrosion in wet environments.

Black-oxide steel coupling nuts have a dark surface color and are mildly corrosion resistant in dry environments.

For technical drawings and 3-D models, click on a part number.

Thread					Each
Size	Pitch, mm	Lg., mm	Wd., mm		1-9	10-Up
Zinc-Plated Steel—Class 8
M27	3	81	41	000000000	000000	000000
Black-Oxide Steel—Class 8
M27	3	81	41	000000000	00000	00000

Metric 18-8 Stainless Steel Coupling Nuts

Stainless Steel

Black-Oxide Stainless Steel

Made from 18-8 stainless steel, these metric coupling nuts have good chemical resistance and may be mildly magnetic. Also known as extension nuts, use them to connect and extend threaded rods.

Coupling nuts with a black-oxide finish have a dark surface color.

For technical drawings and 3-D models, click on a part number.

Thread					Each
Size	Pitch, mm	Lg., mm	Wd., mm		1-9	10-Up
18-8 Stainless Steel
M27	3	81	41	000000000	000000	000000
Black-Oxide 18-8 Stainless Steel
M27	3	81	41	000000000	00000	00000

Brass Coupling Nuts

These coupling nuts are corrosion resistant in wet environments, electrically conductive, and nonmagnetic. Also known as extension nuts, use them to connect and extend threaded rods.

For technical drawings and 3-D models, click on a part number.

Metric

				Each
Thread Size	Lg., mm	Wd., mm		1-9	10-Up
Brass
M27	81	41	000000000	000000	000000

Stainless Steel Extra-Long Coupling Nuts

These coupling nuts have good chemical resistance. Also known as sleeve nuts, they're at least twice the length of standard coupling nuts to provide more room to connect and extend long lengths of threaded rods.

For technical drawings and 3-D models, click on a part number.

Metric

Thread							Each
Size	Pitch, mm	Lg., mm	Wd., mm	Threading	Min. Thread Lg., mm		1-9	10-Up
18-8 Stainless Steel
M27	3	162	41	Partially Threaded	27	000000000	0000000	0000000