Park designed the perfect shop hammer!
The HMR-4 has a fiberglass shaft, a soft touch rubber grip, and a two-sided head—steel on one side and a replaceable plastic head (part #293) on the other side
The HMR-4 is nominally 2 pounds (885 grams) and is 13.5" long (345mm).
The steel striking face is about 1-3/8" diameter (35mm) in diameter.
The plastic face is 1-11/16" (43mm) in diameter.