These fit the Celestron 93493 tripod, which was used on the Celestron CPC 9.25 XLT mounts, and perhaps some others. The tripod leg (after you pull out the "foot") slides into the ScopeRoller, and three bolts lock the ScopeRoller into position on the tripod leg. There has been some variation over the years in Celestron's leg designs, so if your feet look the picture below, and the outside diameter of the tripod leg is 1.42" (and the foot is 1.63" outside diameter), this is the right one for you. (If the feet don't come out, or the leg is a different size, contact us, and we'll see what we can do to meet your needs.)
Celestron 93493 Tripod Leg & Foot