This is a nice clean example of a Heller Brothers 10" spring loaded, self-adjusting masterwrench (pipe wrench). This one does have a small portion of the end of the handle cracked off and a small chip of the moving jaw, but otherwise is in useable condition with a good pivot joint, and spring loaded jaw. It has a spring loaded jaw that ajusts to the smaller pipe sizes as presure is applied to the handle. The serated jaws are in good condition like the rest of the wrench. It's marked "HELLER NEWARK N.J. U.S.A. 4-14-25 7-11-41 MADE IN U.S.A. CHROME VANADIUM 10" MASTERENCH" and some other patent dates. We note that the Heller name is almost completely ground off, not sure why, appears to have been done at the factory where is was made. It may be that another manufacturer used the tooling to cast this wrench, and Heller didn't want their name on something that wasn't made in their facility. This happened during war production, when a given plant could not produce enough tools to meet the demand for a short period of time the maker would job out manufacturing to other maker's with capacity. The trade name sounds like Masterwrench, but the WR is dropped in the actual trade name. There is also a Heller logo near the name (standing horse). A clean older wrench, some very minor staining or darkening to the finish, no rust, straight not bent, in very good working order with a strong adjustment spring!