Jacobs 31090 Keyed Drill Chuck 0-3/8" Capacity with K30 Key. It is designed with a 1/2-20 threaded mount, providing compatibility for various power tools and stationary drilling machines. The one-piece sleeve design eliminates cracks between driving teeth, while the through-hardened sleeve, nosepiece, and keyholes provide exceptional wear resistance, making this chuck ideal for extended use.
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