No battery, replaced stock button with we msk button. No flash hider, but threads are still good. Hand guard is custom CNC aluminum (was made before A&K released it). Pin doesn’t like to stay in on the metal hand guard, but you can buy one for 3 bucks (msk body pin on evike). Runs perfectly, just a little noisy (stock internals) Eotech doesn’t work, something wrong with electronics, just throwing it in with the kill flash. The mags are the stock 300round pmag it comes with and 2 king arms mid caps.