Airsoft Atlanta got the Acetech Raider Tracer Unit with the Blaster-M found inside in stock... "The Acetech Raider Tracer Unit (Blaster-M Inside) is for use on airsoft guns that have a 14mm threaded (for use on 14mm CCW or 11mm CW w/included adapter) barrel. Built-in battery that's rechargeable with USB (included).