Quick locking and releasing attachment retainer

An attachment retainer having a collar that, when at a collar locked position, has a first surface that is positioned above an open end of a passageway of a spindle to assist in retaining locking members in locking engagement with a driven tool. When in a collar release position, a second surface of the collar is positioned above the open end of the passageway to provide a space to receive a portion of the locking members so that the locking members can be disengaged from the driven tool. A plunger is displaceable to a position beneath another opening of the passageway to assist in retaining locking members in the passageway. A cam surface of a release ring can engage, and facilitate linear displacement of, release members as the release ring is rotated, which can facilitate axial displacement of the collar from the collar locked position to the collar release position.