Metallics JLWI3 Washers 6 Int Tooth Lock St-zn (Jar 100)

The JLWI3 is a #6 internal tooth lock washer, so it fits #6 machine screws and #6 sheet metal screws. Ordering the wrong number here is the usual mistake: a #8 washer on a #6 screw lets the head pull through the teeth and you lose the locking action entirely.

Internal tooth, which is what the JLWI3 is, keeps the teeth under the screw head where they bite into the head and the mounting surface without showing. External tooth washers put the teeth outside the head for a wider bite and more locking grip on soft or painted surfaces, but they are visible and can catch. For a #6 ground or device screw in a box, the internal tooth is the usual pick because it seats cleanly under a small pan or round head.

They are zinc plated steel. That handles interior electrical work, panel and box mounting, and dry mechanical rooms. For sustained wet or exterior exposure, zinc plated steel will eventually corrode, so a stainless washer is the better call there.

100 pieces per jar. The jar pack is what makes it useful for a van or shop bin, since #6 lock washers get consumed a handful at a time on device and ground screws rather than by the box.

Metallics lists the JLWI3 for the electrical, plumbing, heating and air conditioning trades. In practice that means device and cover screws, small panel and enclosure hardware, control wiring terminals, and bonding screws where vibration would otherwise back a #6 screw out.

The jar is listed at 3 x 3 x 2.15 inches and 0.1 lbs. Small enough to sit in a van drawer or a parts bin with the rest of the fastener jars rather than taking a shelf.

They are built to ANSI dimensions for a #6 internal tooth lock washer, so the inside and outside diameters match what a standard #6 pan or round head screw expects. That matters if you are mixing stock from more than one supplier across a facility.