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McMaster 91190A530 Black-Oxide Steel Split Lock Washer, for M5 Socket Head Screws, 5.4 mm ID, 8.8 mm OD, Pack of 100

UPC: | Harmonization / Schedule B : 7318.21.0030

Country of Origin: | Shipping Weight: 0.082 lbs

Original price $45.47 - Original price $45.47
Original price
$45.47
$45.47 - $45.47
Current price $45.47

Stop socket head screws from loosening due to mild vibration. These washers have a small diameter to fit under screws with narrow heads, but are still thick enough to keep fasteners secure. While they're not as vibration resistant as other lock washers, they are a great fit for electrical panels, light fixtures, and other light duty assemblies. Split lock washers are not reusable, and they only work with fasteners that have right-hand threads. Also known as high-collar lock washers.

Black-Oxide Steel—Best for dry environments since moisture will cause these washers to rust. They have a dark, matte appearance.

For Use With Socket Head Screws
For Screw Size M5
ID 5.4 mm
OD 8.8 mm
Thickness 1.5 mm to 1.7 mm
Finish Black Oxide
Hardness Rockwell C44
Material Steel
Specifications Met DIN 7980
System of Measurement Metric
Washer Type Split
Country of Origin United States, Belgium, Canada, China, France, Germany, India, Indonesia, Italy, Japan, Malaysia, Mexico, Philippines, Poland, South Korea, Switzerland, Taiwan, Thailand, Vietnam
DFARS Compliance Specialty Metals COTS-Exempt
Export Control Classification Number (ECCN) EAR99
REACH Compliance REACH (EC 1907/2006) (02/04/2026, 253 SVHC) Compliant
RoHS Compliance RoHS 3 (2015/863/EU) Compliant
Schedule B Number 731821.0000
U.S.–Mexico–Canada Agreement (USMCA) Qualifying No