Cobalt Drill Bits Set 145pcs M35 HSS 135 Degree Tip - Complete Kit

In this review of the 145Pcs Cobalt Drill Bits Set the bottom line is straightforward: this kit is best for hobbyists, metalworkers and home professionals who need a wide range of sizes and tougher bits for hardened materials. The set's single biggest reason to buy is the industry grade M35 high-speed steel composition with 5% cobalt, which offers noticeably better wear resistance than standard HSS in many shop tasks. The included indexed storage case and the full range from 1/16 to 1/2 in plus letter and numbered sizes make it convenient for repeated use.

Key Features

• Comprehensive size range: The 145 pieces include fractional sizes from 1/16 to 1/2 in in 1/64th increments, letter sizes A to Z and numbered sizes #1 to #60 for nearly any common drilling need.
• M35 cobalt alloy: The bits are made with 5% cobalt content for improved wear resistance and longer life when working hardened metal and stainless steel.
• 135 degree split point: The fast cutting 135 degree tip centers quickly and reduces walking, so holes start cleaner with less pressure.
• Precision grinding: Fully ground flutes and a twist design provide a sharp cutting edge and faster chip evacuation for more consistent drill performance.
• Organized storage case: A hard outer case with a size index and a drill bit holder keeps the set organized and easier to transport between jobs.

Who It's For

The set suits DIYers, machinists and general contractors who frequently drill into hardened metal, cast iron and stainless steel as well as wood and plastic. Its broad size coverage makes it handy for repair shops, fabrication benches and home tool collections where you want one kit to cover most needs.

It is less suitable for users who need only a few specialty sizes or who expect carbide-level performance for extremely abrasive composites; some customers report variable durability and occasional breakage if bits are abused or used without correct speeds and feeds.

Pros & Cons

Pros

• Wide selection of fractional, letter and numbered sizes covers most drilling tasks without buying single bits.
• M35 alloy increases hardness and improves cutting life compared with standard HSS in many metal drilling jobs.
• 135 degree split point and precision grinding reduce walking and improve hole quality out of the box.
• Organized storage with size index keeps bits accessible and protected during transport.

Cons

• Some users report the bits can dull or break if used at wrong speeds or on very hard jobs; technique and feed rates matter.

Specifications

Set contents	145 pieces: fractional 1/16 to 1/2 in, letters A-Z, numbers #1-#60
Material	M35 high-speed steel with 5% cobalt
Tip angle	135 degree split point
Shank type	Universal round drill shank
Storage	Indexed drill bit holder and outer storage case
Applications	Hardened metal, cast iron, stainless steel, plastic, wood

Our Verdict

The 145Pcs M35 cobalt drill bit set is a practical, cost-effective kit for people who need broad size coverage and tougher bits for metalwork. While technique affects bit life, the M35 construction, 135 degree tips and organized case deliver strong value for workshops and serious DIYers who want one versatile collection rather than multiple single bits.

Frequently Asked Questions

Are these bits suitable for stainless steel?
Yes. The M35 cobalt alloy and 135 degree split point make them better suited to stainless steel and other hardened metals than basic HSS bits.

Does the set include metric sizes?
No. The kit contains fractional inch sizes from 1/16 to 1/2 in, letter sizes A to Z and numbered sizes #1 to #60.

Is a case included for storage?
Yes. The set ships with an outer storage case and an indexed drill bit holder for organized storage and transport.