a device for preparing multiple channels in a bone comprises a handle , a single guiding sleeve mounted removable at said handle and an arm projected from said handle . said single guiding sleeve comprises a central first guiding channel for receiving a first aiming wire , a second guiding channel for receiving a further aiming wire , said channels have parallel axes . at least one cannulation is provided , a central longitudinal axis thereof runs at a distance and parallel to the guiding channels . said at least one cannulation being arranged offset in a circumferential direction to said second channel . an aiming wire introduced in said second channel can be replaced into a cannulation by pulling off the guiding sleeve turning it about the first aiming wire and reinserting the turned guiding sleeve into said handle .