The APS ASR112 or also known as the APS M4 Guardian 8.0 EBB gets featured in Evike.com's "The Gun Corner"... "The new 2015 models come with APS's newest Silveredge gearbox. The all new APS Silver Edge Gearbox utilizes a unique polishing technique to remove burrs and surface imperfections from the gearbox shell. This polishing leads to an incredibly smooth and even finish that will reduce friction and lower the gearbox load.