Somewhere between installing your ShockCollar and admiring the finished build, a screw made a break for it. Rolled under the bench, got sucked into the shop vac, whatever — it happens to everybody. That's what this bag is for. Exact replacement hardware for the One Hundred Concepts ShockCollar. Same sizes, same thread, no hunting through a hardware store bin hoping something's "close enough." What's in the bag: 1 nut, 4-40 1 screw, 4-40 x 5/8" 1 screw, 4-40 x 1/2" 1 screw, 4-40 x 3/8" Grab an extra bag while you're at it. You'll probably need it.