measure circumference of extended knee and elbow and match to the sizes listed below:XS- Knee - 11-13 in Elbow - 6-8 inS/M- Knee - 13-15 in Elbow - 8-10 inL/XL- Knee - 15-17 in Elbow - 10-12 inPRO TIP: If your measurements are in-between the sizes shown or you’re simply in doubt

7071 Aluminum and 3056 steel axles provide performance that is tried and true

5mm Allen key or standard 9/16” hex wrench

Ultra Light Weight Titanium Axle: Solid Ti64 Titanium axle saves weight while maintaining a high level of strength and rebound

surfaces stay smooth and fast

Spitfire F4 99a Formula Four Conical Full 52mm White Blue Wheels GIFTS-BOSS measure circumference of extended kneeSpitfire F499a Formula Four Conical Full 52mm White Blue Wheels