This is a really simple safe way to use a compound bow. It uses the bolt that holds the arrow rest as a anchor and you pull the string up to a sear controlled with a trigger. It has safety and a dry fire prevention. It allow you to hold at full draw for a long period as needed for shooting from a tree stand. Or if your getting older and are loosing arm and shoulder strength, you can still enjoy the sport without the struggle of pulling a heavy bow. It basically turns a compound bow into a vertical cross bow. Look up Drawloc on the net there is lots of info and videos