Abstract: The present invention discloses a knob-like collar device adapted to fit securely around the lateral displacement locking sleeve of a quick-release hose coupler. The device promotes one-hand operation of the coupler by providing purchase and grip for the thumb of the hand holding the coupler thereby facilitating the lateral displacement of the locking sleeve. The device is particularly useful when the coupler is very cold, a condition that commonly results from the high velocity passage of fluids or gasses through the coupler. The device also absorbs mechanical shock resulting from the accidental dropping of the coupler on a hard surface, thereby protecting the coupler from damage.