The part number is N196034  This N196034 Keyless Drill Chuck Clamps Bits From 1.5mm To 13mm In Diameter, Fitting A Variety Of Drill Bit Sizes For Multiple Tasks.  Carbide Tipped Jaws Grip Bits Firmly While Minimizing Jaw Wear For Long-lasting Performance Even With Heavy Use.  it fit to DCD796D2BT Type 1, DCD797B Type 1, DCD797D2 Type 1, DCD910KX Type 1, DCD920KX Type 1, DCD940KX Type 1, DCD951KL Type 1, DCD960KL Type 1, DW971K-2 Type 6, DW972B Type 6, DW972K-2 Type 6, DW972KQ-2 Type 6, DW980K-2 Type 1, DW983K-2 Type 1, DW987K-2 Type 1, DW990K-2 Type 4, DW990KQ-2 Type 4, DW995K-2 Type 6  Compatible with: 966 Type 1, 977 Type 1, 978 Type 1, 984 Type 1, 987 Type 1, 9877 Type 1, 9877 Type 2, 9887 Type 1, 9887 Type 2, 9966 Type 1, 9977 Type 1, 9978 Type 1, 9984 Type 1, 9987 Type 1, CMCD720B Type 1, CMCD720D2 Type 1, CMCD721B Type 1, CMCD721D2 Type 1, DC920KA Type 1, DC920KA Type 1, DC930KA Type 1, DC930KA Type 1, DC940KA Type 1, DC940KA Type 1, DC980KA Type 1, DC983KA Type 1, DC984KA Type 1, DC984KA-AR Type 1, DC984KA-B2 Type 1, DC984KA-BR Type 1, DC984VA Type 1, DC985KA Type 1