DURABLE & STURDY, solid high speed steel construction, close to impossible to snap compared conventional drill bits, the unique 3-sided shank step drill bits prevents slip in drill chuck and reduces shocks; oiling the titanium stepped bits recommended before every use to maximize the service life.

JAM-FREE PERFORMANCE, dual-flute design and three-sided shank design is optimized for cordless drills in high speed provides greater speed and control while minimizing iron scurf flying around, to lengthen service life, please do not set drilling speed at its maximum to avoid damage to the step bit's cutting edge.

ONE BIT FOR ALL, every stepping bit comes with 10 sizes so you can drill up to 10 holes with different diameters, saving you time and efforts to change bits, every package comes with 5 bits, that makes it 50 diameters in total.

UNIVERSAL COMPATIBILITY, designed for drilling on metal sheets(including iron sheet, aluminium alloy sheet, excluding steel sheet) up to 0.08 in., acrylic, aluminum, PVC and wooden boards up to 0.2 in.; marked with obvious marks for easy and precise hole drilling, compatible with drills 1/4",3/8",1/2".

ALUMINUM CASE, comes nicely in a well-organized aluminum case for easy storage and transport. Keep all of these step drill bits well organized is really an easy project.