15 Pro Cobalt Drill Bit Set 15, Cobalt Pro Drill B 8 percent cobalt high-speed steel construction for superior abrasive resistance in tough metal135 degree split point reduces feed pressure for faster drillingDurable rubber-sided case for added impact resistance, convenient storage and longer bit lifeCase has sliding latch that prevents spilling and a rubberized grip for easy handlingIncludes two 1/16 in., one 5/64 in., two 3/32 in., one 7/64 in., two 1/8 in., one 9/64 in., one 5/32 in., one 3/16 in., one 7/32 in., one 1/4 in., one 5/16 in. and one 3/8 in.