M35 Four Spiral Flute Step Drill Bit Set 1/8ft-7/8ft - High Durability

Our review of the M35 Four Spiral Flute Step Drill Bit Set finds it best suited to DIYers and tradespeople who need a reliable multi-size bit that handles tougher metals as well as softer materials. The single biggest reason to buy is the M35 cobalt construction combined with a four-flute design and new TiAlN coating, which together deliver longer life and cleaner, faster cuts when drilling through stainless steel, aluminum, wood or plastic. The set simplifies hole sizing with 34 steps across three bits and includes a 1/4' hex shank for secure fit in standard chucks and impact drivers.

Key Features

• M35 Cobalt Superhard Steel: Provides high wear and heat resistance so the bits stay sharp longer when cutting stainless steel and other hard metals.
• Four Spiral Groove Design: Four cutting blades and spiral flutes remove chips efficiently for smoother, faster drilling and reduced clogging.
• TiAlN Coating: A modern coating increases surface hardness and reduces friction, improving thermal performance under heavy use.
• Wide Range of Sizes: Thirty four step sizes across the three bits let you drill multiple hole diameters without swapping tools for many common tasks.
• 1/4' Hex Shank: Hex shank provides secure grip in drills and impact drivers so the bit resists slipping during high-torque work.
• Customer Support Warranty: The seller offers responsive support and a warranty policy that promises refund or replacement if the hex shank breaks.

Who It's For

The set is ideal for homeowners, metalworkers and fabricators who need a compact solution for drilling a variety of hole sizes in thin stainless steel, aluminum, plastics and wood. It is especially useful when you want to avoid swapping individual twist bits for incremental sizes because the step design covers multiple diameters in one tool.

Those who should look elsewhere include users who must drill deep holes through very thick plate or masonry, or those needing precision tolerance holes for machine parts where a dedicated twist or reamer per diameter is preferred. For very soft materials where shredding is a concern, separate specialized bits may still be better.

Pros & Cons

Pros

• High wear resistance from M35 cobalt steel that keeps edges sharper during repeated metal work.
• Four-flute geometry and TiAlN coating combine for smooth cuts and efficient chip evacuation.
• Wide size coverage across three bits reduces the need to change bits for many common hole diameters.
• Hex shank fits securely in impact drivers for faster jobsite use and easier bit changes.

Cons

• Step bits are intended for thinner materials; cutting through very thick stock requires different drill bits or multiple passes.
• The stepped design gives less precision for tolerance-critical holes compared with individual ground twist or reamer tools.

Specifications

Material	M35 cobalt high speed steel (SKH55)
Coating	TiAlN industrial-grade coating
Shank Type	1/4' hex shank
Size Coverage	34 sizes across three step bits (1/8' to 7/8' ranges)
Flute Design	Four spiral cutting blades
Compatible Materials	Stainless steel, aluminum, wood, plastic
Warranty/Support	Responsive support with refund or replacement if hex shank breaks

Our Verdict

The M35 Four Spiral Flute Step Drill Bit Set is a durable, versatile option for users who frequently drill a range of hole sizes in sheet metal and general workshop materials. Its cobalt construction, four-flute design and TiAlN coating deliver noticeably smoother cutting and longer life than common HSS step bits, offering solid value for DIYers and light industrial use. Choose this set when you want fewer bit changes and reliable performance on tougher metals.

Frequently Asked Questions

Can these step bits cut stainless steel?
Yes. The M35 cobalt composition and TiAlN coating are designed to handle stainless steel and other hard metals when used on appropriately thin stock.

Will the 1/4' hex shank fit impact drivers?
Yes. The 1/4' hex shank is compatible with standard drill chucks and impact drivers for secure use.

How many hole sizes do the set cover?
The three bits include a total of 34 step sizes covering ranges from about 1/8' up to 7/8' to meet many everyday drilling needs.