A collar for a clutch, particularly a clutch used in selectively connecting and disconnecting a source of drive torque with a co-axial driven shaft. More particularly, the present invention relates to a collar wherein meshing surfaces of the torque source and the driven shaft are designed such that the collar is under a neutral axial force while under torque. The shift collar is splined to a rotating shaft and is slideable along the direction of the longitudinal axis of the shaft. Translation of the shift collar is preferably performed by means of a shift mechanism in association with a detent ball, used to self-lock the shift collar in place under torque load. When the shift mechanism and detent ball are moved to release the shift collar, the angle teeth and splines cause the shift collar to disengage, even under high torque load.