I have the Army TM 9-1005-319-23&P (Unit and Direct Support Maintenance Manual) for the M16A2 and M4. On page 2-53, there is mention of a "Swivel Mount" that is to be mounted on the opposite side of the shooter's hand to better facilitate handling of the weapon. It attaches in the area between the two arms of the front sight, and attaches directly to the barrel. The sling swivel is removed form the front sight assembly and added to this swivel mount.
See entire page here.I was wondering if anyone else has seen this piece of equipment, and if so, where? I'd like to get one, as this appears to be a part of M4geries that appears to be not very common/reproduced. I want mine to be ACCURATE, or as close to M4 as possible.

Thanks!