Quick view Desert Tech Desert Tech Quattro-15 Lower 556 Blk $281.85 The Quattro-15 lower receiver accepts the Quadmag-53" Desert Techs 53 round magazine and standard AR pattern mags. The Quattro-15 lower receiver is drop in capable with all standard AR-15 upper receivers.Features : Fits Milspec AR15 Uppers Accepts... Compare Add to Cart