Atoplee 1pc Semi-automatic Mini Hand Drill Chuck Micro Twist Hobby Craft Jewelers Hand Tool with 20pcs 0.3-1.6mm Twist Drill Bits Set Full metal. Self-driven turbine, hand drill automatic, accurate and efficient. High-precision, double-chuck, it can clip the drill of 0.2~2.0mm. Hand-pressure rotary drilling, time-saving, convenient and quickly. It can drill on the amber, beeswax, wood, plastic, walnut, rubber, and other materials. Structure: the body is steel, the chuck is alloy metal, the main stem is spiral and equipped with backspring. Color: Silver Length: 11cm Chuck clamping range: 0.2-2.0mm Use shank typer: round handle The shape of the drill shank: round only Twist drill bit Material: HSS high-speed steel 4241 Crafts: grinding Shank Diameter: 0.3mm 0.35mm 0.4mm 0.45mm 0.5mm 0.55mm 0.6mm 0.65mm  0.7mm 0.75mm 0.8mm 0.85mm 0.9mm 0.95mm 1.0mm 1.2mm 1.3mm 1.4mm 1.5mm  1.6mm Positioning firstly when punch for smooth objects. When punch for the harder objects, make a hole with a small dril firstly, then expanded it to a larger hole. It is normal if it is a little tight when matchs with 2.0 grill, just force open the chunk a little. <span class="a-text-bold">Note</span>: Wearing protective tools when use it and pay attention to the emergency  situation. Please keep the exertion directions are always  perpendicular, or the drill bit is easy to be broken. This product is not suitable for drilling on agate, jade, metal, steel and other hard materials, slip or unusable may happen.