The M16A2 Buttstock is about 5/8" of the inch for a longer period then the earlier types. Due to the enhanced size it employed an extended buttstock screw plus a spacer. The swivel is mounted nearer for the buttplate. This buttstock is currently utilized over the M16A4: Individually, I would https://riverxcagf.bcbloggers.com/30754697/colt-m16a1-for-sale-things-to-know-before-you-buy