They aren't cheap but easy to sell on once you stop using them.Don't forget you will also have to buy a heavy duty battery also pretty expensive. If you want to go cheaper you can get a set that work off your car once you have drive up on them. Keep a look out in the adds as they sometimes come up for sale from ex racers. Best invention since sliced bread in my opinion. Can't believe all the years I spent running up and down the race paddock trying to start my bikes. Mind you I was younger then!