Sinyeenglon Cobalt Drill Bit Set – 99 Pcs M35 HSS for Hardened Metal & Stainless Steel, 1/16-3/8 in

Overview

The Sinyeenglon Cobalt Drill Bit Set blends the toughness of M35 cobalt with precision grinding to deliver fast cutting and lasting edges when drilling through hardened metal and stainless steel. This comprehensive 99-piece assortment arrives in a robust plastic index case designed for organized storage and quick access between tasks in both workshops and professional garages.

Key benefits at a glance

• High performance material: Cobalt M35 delivers a hard, sharp edge that resists wear and maintains cutting efficiency over time.
• Durable cutting edge: Hardened full grinding increases wear resistance, helping maintain accuracy across multiple materials such as stainless steel, cast iron, zinc alloy, titanium, aluminum, and other hard metals.
• Longer tool life: Designed to cut faster and last longer, with life often surpassing standard HSS variants in challenging metals.
• Thoughtful packaging: A hard, thick plastic box keeps bits protected and organized, with a compartmentalized layout that stays secure during transport.
• Easy access and clear sizing: Sizes are stored in dedicated compartments, and the bottom of the lid features size indicators for quick selection.

What you get

• A broad size range from 1/16 to 3/8 inches, including common increments to cover many drilling needs.
• Comprehensive coverage for metalworking tasks, from light aluminum work to tougher stainless steel and hard metals.
• Value-packed storage solution that consolidates your drill bits in one place for efficient workflow.

Usage tips

• Keep the drill bit vertical to the workpiece for clean, accurate holes.
• Operate at lower speeds, typically between 200 and 1000 rpm, depending on material and hole size.
• Use cutting fluid or coolant to help maintain a cooler bit temperature and extend life.

Whether you’re outfitting a home shop or upgrading a professional workstation, this set offers a versatile, durable option for demanding drilling tasks. Consider the possibilities these bits open up for working with tough metals and precision holes.