The Bump School bump hammer is one of the most important tools to own for successful lock bumping. With its counter-weight design using pennies, you are guaranteed to find the ideal force and follow-through for any type of lock. Where locksmiths previously used to have to carry multiple bump hammers and objects to span the range of light force / light follow-through to heavy force / heavy follow-through, and every combination in between, now can be consolidated to the Bump School bump hammer. This was designed by locksmiths, for locksmiths, with a lot of engineering for the field. Such features include solid molded design to ensure durability, counter-weight cavity sized to be able to use pennies as the adjustable weight, the counter-weight cap can be opened with a coin or the back of a key, scalloped grip that enables you to swing the hammer from as far up or as far back as desired to adjust required follow-through, manufactured with solid ABS plastic as ABS was found to have the best results. The Bump School bump hammer will be the only bump hammer you will need to buy.