These parts go on the inside of a 2 piece fiber optic photo eye cable assembly. The cable screws apart in the middle & they align the ends when they reassembled. These parts are about the size of a dime & what happens is they get dropped & lost. When lost we must purchase an entire photo-eye assembly, @ $350, as this part cannot be bought separately. These parts were coded using the offset copy tool. I sure am glad WD pointed me in that direction. :-). I am also including a screen shot of TurboCAD/CAM & Mach3 CNC Controller, the image is quire large as I have a dual monitor setup at work.