Putting, fast replaceable SDS Max drills for pneumatic rotary hammers have a 18 mm diameter of a shank and have 5 oval-shaped grooves, from which on one side there are 2 closed and 3 open grooves. In order to calculate from the total length of a drill its pararell length, one has to substract 130 mm from the total length. This is the length at which the drill is putted on the hammer.