An end pin for a stringed musical instrument such as a cello, bass or the like having an end pin receptacle at the base end thereof. A first or conical member is slidably mounted on an elongated rod and has a tapered upper end portion which is inserted into the end pin block or receptacle at the base of the instrument. A second or clamping member is threadably secured to the lower end of the first member and tightened thereon which causes a segmented collet portion on the first member to be moved into engagement with the rod to positively maintain the rod in selected longitudinal positions with respect to the instrument.