Metallics HSSCN11E Drill Bit HD Cobalt St 135d SplPt #11 3-1/2" YLW (1pc)

Cobalt is the right choice for stainless, spring steel, and hardened strut or angle iron. The HSSCN11E is a heavy duty cobalt bit, meaning the cobalt is alloyed through the steel rather than coated, so it holds its edge at the higher temperatures those materials generate and it can be resharpened without losing the alloy. Carbide only becomes necessary in masonry or on abrasive non-metals, where a twist bit of any steel grade is the wrong tool.

A 135 degree split point self-centers, so it starts on its own without a center punch and won't walk across a smooth panel, enclosure face, or round conduit. The flatter 135 degree angle also spreads the cut over more of the lip, which is what you want in hard metals. A 118 degree point needs punching first and tends to wander. On the HSSCN11E that split point is what makes it practical for drilling out stainless fasteners or hitting a tight layout mark in a panel.

One bit per order. The HSSCN11E is a single piece supplied in a pouch, not a boxed index set, which is how electrical shops normally replace the one size they burned through rather than rebuying a whole case.

Order Metallics part number HSSCN11E. That one number covers the #11 size, cobalt heavy duty construction, 135 degree split point, straight shank, and 3-1/2 inch length, so there are no options to specify after it.

The yellow is how cobalt bits are identified in a drill index or on the truck, so a #11 cobalt doesn't get mixed in with plain high speed steel of the same size. It isn't a hard coating like titanium nitride, and the body underneath is cobalt alloy steel throughout.