These are CSI shocks raced for one season in Heavy 160 on a Bullrider. They are the old numbering system with #2s on the left and #7s on the right. Looking at the dyno sheets (included) they are equivalent to 2/3 on the left and 4/2 on the right in the new CSI numbering system. Never wrecked and they are as nice as the day they came from CSI. Won the Heavy 160 Championship at HQMA for 2015 on these shocks and then the boy decided he wanted to do other sports. No need to leave them lying around collecting dust. Can't guarantee what they will do for you, but the first time we bolted CSIs on our car I was simply amazed that they could make that much difference. You can buy this same set from CSI for almost $1000 or you can buy these for a lot less and get the same results.