I got to play with this machine yesterday at the shop and boy is it SWEET! It basically sets your pins for you. You first chrono your bow, weigh your arrow, take a few measurements i.e peep to sight housing, peep to nock point. You punch all those into the machine and it spits out a piece of paper. You then unbolt your sight and there are marks on the paper that you line the pins up with. You have to have your 20yd pin set first though. It's really cool, it had my pins dead on out to 60yds on my 337. It's spot on too, pretty neat. He said it costs about 600bucks just for the machine. Also tells you how much KE you have at all of your pin yardages.