I am not sure who the maker is, but they look very similar to the PITTSBURGH brand that is sold by Harbor Freight Tools.
I have more than one pair of calipers if you need them.
This stainless steel dial caliper measures outside and inside depth and step measurements up to 6 in. with 0.001 in. accuracy. Measurements are easy to read via the sliding scale and mechanical dial. Shockproof and lockable head,
Use for inside, outside, depth and step measurements
Accurate to 0.001 in.
Stainless steel frame
Shockproof and lockable head
1-9/16 in. outside jaws - 3/4 in. inside jaws