Klein Tools KTSB15 Step Drill Bit 7/8 to 1-3/8 in - Durable, Clean

Our review of the Klein Tools KTSB15 step drill bit finds it best suited for electricians, metalworkers and hobbyists who need reliable, clean holes in sheet metal and electrical boxes; the single biggest reason to buy is its combination of a durable aluminum titanium nitride coating and a 3/8-in hex shank that delivers long life and a secure grip under load. The bit's laser-etched step markings and non-walking tip make accurate starts and repeatable holes straightforward, so a tradesperson can depend on it for install work and quick sheet metal modifications.

Key Features

• Durable coating: The aluminum titanium nitride finish offers far greater wear resistance than black oxide, extending useful bit life under repeated cuts.
• Double flute design: Two straight flutes eject chips efficiently for cleaner cuts and less burring when drilling thin metal.
• Secure hex shank: The 3/8-in hex shank resists rounding in the chuck and provides a positive grip for higher torque and controlled drilling.
• Laser-etched markings: High-visibility step markings and targets let the user identify primary hole sizes quickly for precise step selection.
• Non-walking tip: The fast-starting tip reduces walking so pilots start accurately without a center punch in many cases.
• Multiple hole range: One bit covers three hole sizes from 7/8 in to 1-3/8 in, reducing tool changes for common panel and box openings.

Who It's For

Electricians and metal fabricators who frequently open and modify electrical boxes, panels or thin-gauge sheet metal will appreciate this step bit; its clean-cutting double flutes and durable coating make it a practical choice for worksite conditions where longevity matters. The clear laser-etched size markings also help installers hit the right hole quickly during repetitive tasks.

Those working primarily in thick structural steel, masonry, or who need many incremental sizes beyond the three primary steps should look elsewhere, since this bit is optimized for sheet metal and the specified 7/8 in to 1-3/8 in range rather than heavy-duty or precision hole saw applications.

Pros & Cons

Pros

• Durable aluminum titanium nitride coating gives noticeably longer life than standard black oxide bits.
• Double flutes provide better chip removal and cleaner hole edges in thin metal.
• 3/8-in hex shank prevents rounding and keeps the bit stable in a drill chuck or impact driver adapter.
• Laser-etched markings and non-walking tip improve accuracy and speed on the job.

Cons

• Not intended for heavy structural steel or applications needing many incremental sizes beyond the three steps.

Specifications

Brand	KLEIN TOOLS
Model	KTSB15
Step range	7/8 in to 1-3/8 in (22.2 to 34.9 mm)
Shank	3/8-in hex
Flutes	Straight double fluted
Coating	Aluminum titanium nitride
Markings	Laser-etched step sizes and targets

Our Verdict

The KTSB15 is a practical, professional-grade step bit for electrical and sheet-metal work, offering long life from its aluminum titanium nitride coating and reliable performance thanks to double flutes, a secure 3/8-in hex shank and clear step markings; it represents good value for those who need quick, clean holes in thin metal but is not a substitute for heavy-duty drilling in thick structural materials.

Frequently Asked Questions

What hole sizes does this step bit cover?
The bit covers three primary hole sizes from 7/8 in to 1-3/8 in (22.2 to 34.9 mm) with laser-etched indicators for the main steps.

Will this bit start without walking?
Yes; the fast-starting, non-walking drill tip is designed to reduce walking and help start holes accurately on thin metal and box openings.

Is the shank durable for heavy use?
Yes; the thick 3/8-in hex shank prevents rounding in the chuck and provides a positive grip for repeated trades use.