NordicTrack Standard Corner Roller / wheel 3" PIN AXLE with flat or flange head on one end that fits into the metal frameFits and is the most common or standard PIN for the lightweight plastic vented corner rollers shown as well as Legacy ski machines with solid corner rollers with brass bushings. USA Ski Machines Only Legacy ski machines with 2 corner wheels which require a 2 5 8" THREADED PIN AXLE which tightens using a flat head screwdriver on other end. If you need a 2 5 8" THREADED on one end PIN AXLE that tightens using a flat head screwdriver Order HERE If you