DEWALT DW5780B15 1-Inch by 18-Inch Cold Chisel Spline Shank
The DEWALT DW5780 18" Cold Chisel 3/4" Hex x 21/32" Round Spline Shank is built of fully hardened steel body which delivers increased life and durability.  For use with all brands of SDS Max demolition hammers and rotary hammers with chipping function.  The Cold chisel (narrow chisel) is used for "channeling" or breaking in a straight line.