Porter Cable PC1801D 18v Ni-cd or lithium-Ion Driil (Bare-tool) 18-Volt Drill/Driver features a single-sleeve 1/2-in chuck High-performance motor and 2-speed gearbox for heavy-duty applications 32-position clutch with micro-adjust gives consistent torque control for driving various size screws 1/2 in. keyless chuck offers excellent bit retention and durability. Compatible with Porter-Cable 18V Lithium or NiCad batteries