A clutch where the output always comes to the same degrees of registry with the input is shown as including coaxial drive and driven members including a hub for mounting on a drive shaft. The drive member is slidably mounted on the hub and rotatable thereby. The drive member is formed with a multiplicity of ball-receiving cavities which are located radially inward of the periphery of the drive member. The driven member includes a carrier member having a multiplicity of balls mounted thereon for engagement with the cavities. The carrier member includes a flat, radial ring portion and an inner annular flange which provides a first degree of safety by tending to prevent any dislodged balls from the carrier member from travelling inwardly between the drive and driven members and tending to allow the dislodged balls to travel radially outward of the clutch. The carrier and drive members have intermeshing interface teeth. The drive member is moved axially on the hub for engagement of the cavities thereof with the balls of the carrier member as the teeth of the drive member engage the teeth of the ball carrier to thereby rotate the driven member. In its most preferred form, a second degree of safety is provided by having the maximum interface gap between the drive and driven members greater than the diameter of the balls to prevent any dislodged balls from jamming between the drive and driven members.