Yanran Multifunctional Step Pyramid Drill Bit with Cobalt Hole Opener Spiral Drill (4-20mm + Twist Drill*1) 2-Piece Set

Recommended for metal thickness up to 5mm; for stainless steel 304, hand drills suitable up to 1mm thickness, bench drills recommended for 2-5mm thickness

Requires continuous cooling with cutting fluid during operation to prevent overheating

Compatible with handheld drills, bench drills, impact drills, and electric drills

Dual spiral flutes for rapid chip removal and reduced cutting resistance

Clear fiber laser marking for easy diameter identification

Universal triangular shank prevents slippage during use

Suitable for drilling and enlarging holes in various materials with high efficiency

Use cutting fluid to cool the drill during operation

Avoid using 12V cordless drills for large diameter holes due to insufficient torque

For stainless steel drilling, avoid metal thickness over 3mm with handheld drills to prevent drill damage and overheating

Industrial drilling and hole enlargement in metals and non-metals including stainless steel, carbon steel, aluminum, copper, plastic, and ceramic tiles

Ideal for manufacturing, metalworking, electrical, and construction industries requiring precise and durable step drills