Laxsoft talks about the Mk-7 Airsoft BFG Sound Device being sold by Curlys Airsoft on Etsy. This is a reusable airsoft sound grenade and needs an M120 or M130 AEG spring and a box of 209 primers before you can use it... "Hello everybody its Lax, and in todays video I will be discussing everyting there is to know about the Mk7- BFG airsoft grenade."