This hammer is made by the Thor Hammer Company in Birmingham UK - their part number is 712R. It has two replaceable 1-1/2" diameter plastic faces - one hard white nylon and the other soft grey PVC. At a weight of 560 g it is one of the most versatile hammers that we have seen - we use it for a variety of tasks including as a chisel hammer, adjusting plane blades, and assembling joints.
Face diameter 38mm 1.1/2in
Fitted as standard with one White and one Soft Grey screw in Face with Wood Handle.