HIGH QUALITY - Premium high speed steel material provides excellent drilling effect, smooth drilling and less burrs. USE WITH - These HSS twist drill bits can be used with electric drill, cordless drill, pistol drill, etc. WIDE APPLICATION - Ideal for drilling on stainless steel, cast iron, sheet metal, steel plate, angle iron; widely used in drilling stainless steel plate, automobile spring steel and die steel. DURABLE TO USE - Hardened cutting edge effectively extends the life of the drill bits. Three-point positioning provides good accuracy, making it easy to drill round holes. AFTER-SALES GUARANTEE - We care about the feelings of every customer. If this product does not meet or exceed your expectations, please contact us first, we will resolve the issue immediately. LRFR is committed to providing each customer with the highest standard of customer service.