All new for the R8 and Beeman- ARH Old HW50. Not the new Euro HW50-HW99-R6. Works with both leather and synthetic seal versions. Factory new or better power. Rear guide with built in spacing, spring, and tar.
Since the piston varies and many short pistons exist, we are building in spacing and using one long guide instead of risking the gun not cocking if you have one of the short piston guns.
If you want a mid power old HW50 kit- Order the HW55 custom kit.