Heald were an American machine-tool company famous for such products as high-class boring machines, internal grinders, rotary surface grinders, boring and wheel heads and cutting tools - for which they gained an international reputation for unsurpassed quality of construction and accuracy in use. Their No. 3 Tool Sharpener was not a conventional tool and cutter grinder, but one intended to sharpen the tools used in the Company's Bore-Matic machines - or any single-point tool of a similar type.