1. Excellent Material 6542 & M2 HSS: this reamer is made of excellent 6542 and M2 HSS material, which is sturdy, and suitable for many metal materials. 2. MULTI-FUNCTIONAL - This reamer is used to align existing holes and enlarge undersized holes before installing bolts or rivets. 3. Wide Application This reamer is suitable for steel, metal, aluminum alloy, brass, plastic, iron, nickel, copper, cast iron materials, etc. 4. 5 Flute Spiral Groove This reamer adopts a 5 flute spiral groove, which is highly efficient and not easy to jam the chip. 5. COMPACT AND PORTABLE - This reamer is small and lightweight, which makes it very convenient to carry and use. Specifications: Item Type: Spiral Flute Reamer Material: HSS6542 and M2 high speed steel Maximum diameter: approx. 3/8 inch/1 cm Package includes: 1 x Spiral Flute Reamer 1 x storage box.