A very nice forged monkey wrench, stamped "oil hardened" on the moveable jaw and "NATIONAL TOOL DIST IBU ORS LTD Toronto Canada" on the body. Mister G pointed out that this clearly refers to "National Tool Distributors" and that the forging die must have somehow worn to produce this odd spelling.
A 1961 catalogue for Continue-Flo Products of Burlington, Ontario indicates that National made a number of different products:
They also seem to have entered into an arrangement with the Nye Tool Company of Chicago to make pipe cutters and pipe vices:
According to a contributor to the Garage Gazette, National was once the supplier of pipe wrenches to Gray Tools, based on a Gray catalogue entry:
He also produces evidence to suggest that the National Tool Company was the successor to the Perfect Pipe Company of Galt, Ontario (now Cambridge).
The second letter "T" in "Distributors" is missing, suggesting that the forging dies were wearing, and that his wrench is earlier than mine where both the letters "R" and "T" are absent from the word.
Notice how straight the handle is. Unless mine represents a "bent pattern," it would seem that mine may have been used by Arnold Schwarzenegger!