CORE DRILL 4" Z-1 2 SPEED CONCRETE CORING DRILL by BLUEROCK TOOLS PACKAGE DEAL COMES WITH 1", 2", 3", 4" BITS PACKAGE DEAL! BLUEROCK 4"Z1 Core Drill & 1-4" Bits Bits included 1", 2", 3" and 4" New improved water hose assembly with metal fittings and hardware for "wet" drilling 1-1/4" 7 UNC Standard Spindle Dual Speed: 2100rpm/950rpm