#4 Hi-Collar Helical Spring Lock Washer is sized to pair with the matching socket head cap screw where a regular split lock washer will not fit the counterbore. The split helical ring compresses as the screw seats, keeping spring take-up under the head and helping resist loosening under vibration. Pairs with our 1960 Series Alloy Steel Socket Head Cap Screws in the same nominal size.
Typical applications include machine assemblies with socket screws, compact counterbored joints, and repair kits, where washer clearance under the socket head is part of the design. Plain carbon steel should be kept dry and oiled; ask about stainless washers as a non-catalog item when exposure matters. Compare Alloy Steel Socket Head Cap Screws when building a complete inch socket-screw order.
Cold Headers has supplied specialty socket fasteners since 1962 and supports exact-size washer and cap screw sourcing. Before ordering, compare the print callout to the nominal washer size and the matching socket head cap screw.
Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.