A hammer drill, also known as a percussion drill or impact drill, is a power tool used chiefly for drilling in hard materials. It is a type of rotary drill with an impact mechanism that generates a hammering motion. A hammer drill, also known as a percussion drill or impact drill, is a power tool used chiefly for drilling in hard materials. It is a type of rotary drill with an impact mechanism that generates a hammering motion. Ultimamac has wide variety of Impact Drill Spare parts. You can get Original Impact Drill Spares under one roof from Authorized and genuine dealer at the lowest price.