$2.50 to make. No change in POI. Turn on with shot inertia. Here is a video of one I made

http://s83.photobucket.com/albums/j308/teenathlete3030/?action=view¤t=Bow026.flv

Instructions are here, read the first 3 pages: http://www.archerytalk.com/vb/showthread.php?t=201870