Superior Electric J016 Mini (0.5 to 8 mm) Keyless Drill Chuck with 1/4" Hex Shank Adapter Color: Black, Shank: 1/4" Clamping Range: 1/32" - 5/16" (0.4mm - 8mm) Thread Mount: 3/8 - 24 Overall Length: 2-3/8" , Shaft Length: 1" Chuck Dimensions: 1-3/8" length x 1" Dia