I have them on my emaxx. My emaxx weights about 11lbs with everything(batteries, wheels) and i used 45wt and it was way to light! i has a few mm ground clearence and when i gave it throttle the back bottomed out. So now i have ordered some 70wt and 80wt from tower and im waiting for that to come. I do jumps so thats why i went quiet alot higher. I would sugest getting 60wt, the shocks come with 3 different pistons, 1 hole, 2 holes, and 3 holes, so you can make it stiffer or softer.