M-122 Tripod Characteristics
This is an M-122 Tripod head
. The most distinguishing feature is the spacing of the Data Plate rivets, 1-13/16th center and the completely flat front leg to head transition area. M-2 Tripods have a curved transition area and different rivet spacing. Most M-2 tripods had the Date Plate on the front leg support. But some late production M-2 tripods and M-2 -> M-122 refurbished tripods may have a Data Plate on the rear slope of the tripod head.
Another look at the M-122 and the distinctive flat transition area from the leg support to the tripod head.