Amongst the SIG MCX rifles that we are eager to see have its airsoft version is the MCX Rattler. It is an SBR with a 5.5" PDW barrel and comes with a ultra thin folding aluminium stock and M-Lok rails. The real deal can fire the 5.56 NATO and 300 Blk. Garand Thumb provides some real steel firing action at the range as well as talk about this SBR.