US Patent 7690323 Gauge head assembly with non-magnetic insert

A gauge head assembly for use with a magnetically actuated dial includes a cylindrical body formed from a magnetic material having a cylindrical sidewall with an threaded outer surface, wherein the sidewall defines an axially extending passage for receiving a tubular insert formed from a substantially non-magnetic material, the insert having a closed first end and a second open end with a collar extending radially outward at the second open end and wherein the insert is secured in the passage with the closed first end adjacent the first end of the body.