The XM8 Prototype was an experimental assault rifle produced by German arms manufacturer Heckler & Koch for a replacement for the aging M16/M4. Testing began in 2003, but the project was canceled in 2005. However, HK marketed the rifle worldwide, resulting in its adaption by the Malaysian PASKAL unit in 2010. The XM8 is made entirely from polymers, which allows the weapon to be light as well as durable. It has a rate of fire of 750 rounds per minute, and fires the 5.56x45mm round, which makes the XM8 very effective at medium to long ranges. While not designed with Picatinny rails, the XM8 can fit an XM320 grenade launcher to the underside of the handguard, as well as being able to fit optics to the top of the carrying handle using a special adaptor.