Jacobs 1/2" Professional Keyless Chuck with 3/8" Mount is a hand tight chuck that makes any 3/8" drill a 1/2" drill. Based on an exclusive patented design, it achieves higher gripping power than standard keyed chucks and improves drill performance. The Jacobs Chuck Manufacturing Company is a recognized leader in the design and manufacture of precision tool and work holding devices for stationary equipment and portable power tools.

• 1/2 In. Professional Keyless Chuck with 3/8 In. Mount.
• Hand tight and makes any 3/8 In. drill a 1/2 In. drill.
• Exclusive patented design achieves higher gripping power than standard keyed chucks.
• Improves drill performance.