Sinyeenglon Cobalt Drill Bits Set – 101Pcs M35 HSS for Hardened Metal & Stainless Steel

Sinyeenglon Cobalt Drill Bits Set: Built for Strength and Precision

Engineered with M35 cobalt, these bits cut through hardened metals more efficiently than standard HSS tips. The cobalt alloy delivers high hardness and wear resistance, helping you maintain a sharp edge through challenging materials. In typical use, many operators report longer bit life and smoother cuts compared with common steel bits, especially when drilling stainless steel and other tough alloys.

The set features a hardened full grinding process that yields tips that stay sharp longer, delivering reliable starts and steady feeds. This design minimizes wandering on tough metals and maintains a clean hole as you work through brackets, housings, or frame components. A broad range of common sizes is included, so you can handle multiple steps of a project without hunting for additional bits.

Key benefits you may notice

• Expanded durability: wear resistance helps extend bit life in demanding metalwork.
• Wide size coverage: 14 commonly used sizes in an organized box for fast access.
• Efficient organization: labeled compartments and a sturdy case keep drills where you expect them.

Practical tips for best results

• Keep the drill vertical: align the bit perpendicular to the workpiece for clean entry.
• Low-speed operation: run at 200–1000 rpm to reduce heat.
• Use cutting fluid: apply coolant to keep the edge cool and extend life.
• Material range: designed for stainless steel, cast iron, zinc alloy, titanium, aluminum, and other hard metals.

What you get and how it's organized

The set arrives in a robust plastic index case with separate compartments. Drill bits are printed and sorted for quick identification, allowing you to grab the right size without rummaging. This organized approach is helpful for projects that require switching between sizes mid-task.

Included sizes at a glance

• 1/16 inch — 16 pcs
• 5/64 inch — 16 pcs
• 3/32 inch — 15 pcs
• 7/64 inch — 5 pcs
• 1/8 inch — 15 pcs
• 9/64 inch — 3 pcs
• 5/32 inch — 6 pcs
• 3/16 inch — 6 pcs
• 7/32 inch — 5 pcs
• 1/4 inch — 6 pcs
• 5/16 inch — 2 pcs
• 3/8 inch — 2 pcs
• 7/16 inch — 2 pcs
• 1/2 inch — 2 pcs