8A Z-Tech Series Head and Neck Restraint Size:L and instead uses keyway grooves

and instead uses keyway grooves on each end to prevent slippage of hubs and so on

Dual compound construction

This bearing is designed to fit around the primary shaft for Rotax DD2 kart engines

or hit the track

Compression Ratio: 9

8A Z-Tech Series Head and Neck Restraint Size:L and instead uses keyway grooves8A Series Head and Neck Restraint by Zamp Racing. This device allows for adjustment to find the perfect fit for your shoulders and profile for the ultimate in head and neck protection. Overview and Features The 8A series of head and neck protection features: Lightweight construction (approx. 900 grams) Dual compound construction, with fiberglass and nylon integrated to make the frame progressive in flex and protection during impact Stainless steel