From the Manufacturer
The Jacobs 1M KL-1JT Stainless Steel Keyless chuck is widely used for medical power tools and stationary machine tools. This Industrial grade quality stainless chuck resists chemical corrosion and potential for hazardous sparking. The Jacobs 1M KL-1JT Stainless Steel Keyless chuck's self-tightening feature automatically increases gripping force proportional to increased torque to prevent tool shank slippage. The chuck capacity is from 0.00-Inch to 0.250-Inch (0.0 Millimeter to 6.0 Millimeter) with No. 1 Jacobs Taper mounting. Like all of Jacobs Special Purpose chucks, each Jacobs 1M KL-1JT Stainless Steel keyed chuck is 100-Percent inspected for performance and precision, and includes a one year factory warranty.