Here is my wood gripped M-4. This is a pretty rare modification to an M-4, and although it is not an official U.S. modification, they are accepted as legit. The commonly accepted history behind it is that this was done on Okinawa some time after WWII. Although, I believe that the Philippines is also a likely source, given the native history with woodcraft. The leather handles were not holding up under the humid, tropical conditions and since the plastic grips had not been introduced yet, someone came up with this very ingenious conversion. The leather grip was removed and replaced with a tropical hardwood. The bakelite spacers were reused and the pommel re-staked to the tang.
My example has had the pommel dipped in a rubberized sealant, the kind you would find on taps,dies and drill bits years ago for shipping and long term storage to protect them from rust. I have no idea who done this, but it is during a fantastic job of protecting it, so I'll leave it alone.