Metallics JLWI6 Washers 1/4 Int Tooth Lock St-zn (Jar 100)

The JLWI6 is a 1/4 inch internal tooth lock washer, so it goes over a 1/4-20 or 1/4-28 bolt or screw shank. Internal tooth means the serrations face inward toward the bolt, so the teeth bite the underside of the head and the mating surface rather than showing at the edge.

That is what toothed lock washers are for. The serrations on the JLWI6 dig into the plated or painted surface under the fastener as it is tightened, cutting through the coating to metal and keeping the joint tight under vibration. Metallics lists the line for electrical, plumbing, heating and air conditioning work.

Internal tooth, like the JLWI6, keeps the serrations hidden under the fastener head. That gives a cleaner look and is the usual pick under a screw head on a panel or device, where the teeth still cut through paint or plating to make the bond. External tooth washers spread the teeth outside the head diameter, which gives more grip area and is preferred when the head is large or the material is soft. For a 1/4 inch screw into a painted enclosure, the internal tooth is the standard choice.

They are zinc plated steel. That handles normal indoor electrical, plumbing and HVAC work, including damp interior locations, but zinc plated carbon steel is not a stainless substitute for direct outdoor exposure or washdown areas.

Each jar holds 100 of the 1/4 inch internal tooth lock washers. The jar itself is a small shop container, roughly 3 inches across and 2.15 inches high, so it drops into a van bin or a tool bag without repacking.

Inch sizing. The JLWI6 is a 1/4 inch washer built to ANSI dimensional practice, so it pairs with standard 1/4 inch UNC or UNF hardware rather than an M6 fastener. An M6 bolt is slightly under 1/4 inch and will have extra play in this washer.

Order by JLWI6. That is the Metallics manufacturer part number for the 1/4 inch internal tooth, zinc plated steel lock washer supplied in a 100 piece jar.