Phase 5 Weapon Systems Extended Bolt Release V2 308, Black Finish, Compatible with .308 DPMS Gen 1 Type Platforms Only (Not Compatible with Gen 2) EBRV2308 The Phase 5 (EBRv2/308) gives the operator the ability to reload quicker" clear jams in a more efficient way and eliminate unnecessary hand movements during various operations. For DPMS type 308 rifles.