These step drills are good quality that work great in boring hole. Perfect to add them to your toolbox.<br><br><strong>Features:</strong><br>Triangle round handle, essential hardware tool for woodworking using.<br>Professional step drill for deburring, chamfering, elliptic hole enlargement.<br>Suitable for punch holes through metal, steel, aluminum, brass, plastic, wood, etc.<br>Oversized spiral groove, which can realize one-time macroporous processing.<br>This drill bit set includes 3 sizes(4-12mm, 4-20mm, 4-32mm), which meet your different needs perfectly.<br><br><strong>Specifications:</strong><br>Material: High Speed Steel (HSS 4241)<br>Surface Treatment: Nitriding Treatment<br>Shank Diameter: Triangle Shank<br>Size: 4-12mm, 4-20mm, 4-32mm<br>Item Weight: Approx. 232g / 8.20oz<br>Package Weight: Approx. 236g / 8.33oz<br>Package Size: Approx. 10 * 6 * 3.5cm / 3.94 * 2.36 * 1.38in<br><br><strong>Package List:</strong><br>3 * Step Drill Bits