Klein Tools KTSB11 Step Drill Bit 7/8 to 1-1/8 in - Durable, Clean

In this review the Klein Tools KTSB11 Step Drill Bit is evaluated for tradespeople and DIYers who need accurate, clean large-hole drilling through sheet materials. The bottom line: this double-fluted step bit stands out for its clean cuts and secure 3/8-in hex shank that resists slipping, making it a practical choice when stepping up to holes between 7/8 and 1-1/8 in. It is best for users who value clear laser-etched size markings and a durable aluminum titanium nitride coating that extends bit life compared with traditional black oxide finishes.

Key Features

• Aluminum titanium nitride coating: Provides up to 10 times greater durability than black oxide, extending useful life under frequent use.
• Double-fluted design: Two straight flutes remove chips efficiently and produce cleaner cuts in metal and other materials.
• 3/8-in hex shank: Thick hex shank prevents rounding in the drill chuck and delivers a positive, secure grip during heavy work.
• Laser-etched markings: High-visibility markings identify primary hole sizes quickly so the operator can stop at the exact diameter needed.
• Non-walking drill tip: Fast-starting tip reduces wandering at startup, improving hole placement and finish.
• Versatile material compatibility: Suitable for steel up to 16 gauge, wood, plastic and aluminum for multipurpose shop or jobsite use.

Who It's For

This step drill bit is aimed at electricians, HVAC installers, metal fabricators and handy homeowners who need to punch 7/8 to 1-1/8 in holes in thin metal, studs and common nonferrous materials. The secure hex shank and clean chip evacuation make it a good fit for corded drills and impact drivers when paired with an appropriate chuck.

Users who require very long-life heavy production tooling or who routinely drill thicker plate beyond 16 gauge should consider purpose-built annular cutters or hole saws instead. Also, if multiple, smaller size ranges are needed, a multi-step set might be more flexible than a single two-size bit.

Pros & Cons

Pros

• Durable coating greatly increases expected life compared with standard black oxide bits.
• Double flutes deliver cleaner cuts and better chip removal for neater holes in metal.
• Laser-etched size markings and a non-walking tip improve accuracy and usability.
• Thick 3/8-in hex shank resists slipping and rounding in the chuck.

Cons

• Some users report mixed long-term durability of the tip under heavy use, so performance can vary with application and technique.

Specifications

Brand	Klein Tools
Model	KTSB11
Hole sizes	7/8 in to 1-1/8 in (22.2 to 28.6 mm)
Shank	3/8-in hex shank
Flutes	Straight double flutes
Coating	Aluminum titanium nitride
Suitable materials	Steel up to 16 gauge, wood, plastic, aluminum

Our Verdict

The KTSB11 is a practical single-bit solution for professionals and serious DIYers who need reliable, clean drilling for 7/8 to 1-1/8 in holes. Its durable coating, clear markings and secure hex shank make it a good value for occasional to regular use; those needing industrial-scale longevity or thicker material cutting should match the tool choice to their workload.

Frequently Asked Questions

Can this bit be used on stainless steel?
It will cut stainless and sheet metal, but performance depends on alloy and thickness; use moderate speed and steady feed for best life.

Will it fit in an impact driver?
The 3/8-in hex shank is compatible with many impact drivers, though a firm chuck or adapter is recommended for heavy loads.

How do I know which step to stop at?
The laser-etched markings on primary sizes are designed to be high-visibility so you can stop drilling at the exact diameter you need.