The xeno xero threaded taper mount is a muzzle device that gives a lightweight minimalist mounting option offering non-negotiable repeatability and a solid return to zero.All this while still delivering the durability expected from a dead air mount.The shorter size decreases its entrance into the blast chamber, maximizing sound performance and minimizing overall weight.The xeno xero is compatible with all dead air xeno adapters.The 1/2-28 xeno xero has a bore size to fit 9mm and smaller projectiles.The 5/8-24 xeno xero has a bore size to fit.46 and smaller diameter projectiles.Model: Xeno