HLF XYL ARP9 Battery Extension The MK-8 contains a blowback

The MK-8 contains a blowback system and a mag prime

Can be mounted on 6B7-1M and 6b47 helmet

or both barrels at once for devastating blasts

and Extendable PDW Butt Stock

Precision Aim: Adjustable scope magnification and sight height for better accuracy

HLF XYL ARP9 Battery Extension The MK-8 contains a blowbackThis ARP9 Battery Extension to provide an additional 35mm of space for most AR toy gun batteries. Made with durable 3d print pla material, this extension is compatible with both xyl arp9 and hlf arp9 gel ball blasters and airsoft guns. Specifications: BrandL XYL Material: 3d print pla. Length: 35mm. COlor: black. Package includes: 1x arp9 battery extension.