Boss Aluminum Hop-Up Kit

The Boss Aluminum Hop - Up Kit from BSB gives you a lightweight, aluminum design with added torsional strength to help withstand tough impacts. Best of all, the lightweight aluminum lasts longer than nylon and plastic spacers.

• Ideal for outdoor and indoor use
• Threaded spacer system enables bearings to spin freely increasing performance
• Added torsional strength to withstand tough impacts.
• Lightweight aluminum lasts longer than nylon and plastic spacers