This high quality 8mm Acme Anti-Backlash Nut Block is a great choice for many projects requiring lead screw linear motion. The pitch and diameter are a perfect combination of high torque and speed. This screw fits the bill for most machine designs and has quickly become a standard on builders. It serves more than one purpose in that it can be mounted to the bottom of a 3mm/1/8 inch plate utilizing M5 nylon insert nuts and 15mm M5 screws or can also be mounted directly to V-Slot utilizing two channels with 15mm M5 low profile screws and two tee nuts. These mounting choices allow for a host of modular machine applications. You can mount this block along any length of V-Slot to create your linear motion. To use the the Anti-Backlash Nut Block - Turn the set screw just enough to take out any play in the Nut Block. Then screw the lock nut on the top of the set screw to lock the set screw in place. colour:black Material:metal size:Nut: 5mm Screw: 16mm Package Contents: 1*T8 screw nut seat 1* nylon insert lock nut 1* thin hex nut 1* fixing screw Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.