The product is a Jacobs Chuck No. 33 5/64-1/2" 2-13mm with a Morse Taper 3 Mt 33 Jt, a high-quality key drill chuck made in Britain. This drill chuck features a 1/2 inch mounting size and a tapered mount for easy and secure installation on lathes or milling machines. As a reliable brand in the industry, Jacobs ensures precision and stability when holding drills in place for various drilling applications. see pictures for more details please see my other listing's for more vintage tools and ephemera
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