Franklin Armory's first piston driven rimfire platform chambered in .17 Winchester Super Magnum. It provides a cleaner and flatter shooting solution for all kinds of pest control. The F17-L R2 Osprey Defense slim piston system automatically adjusts for suppressed or unsuppressed use, no adjustments needed. This pairs for use with the 20 barrel, threaded in the common 1/2-28 tpi with compatible suppressors. features an optic ready receiver, standard charging handle, custome tuned trigger, low profile gas block, 15 handguard features an integrated barrier stop/indexing point and is M-LOK compatible.