Great Grips Door Knob Grippers make any standard round doorknob easy to turn with a closed fist, elbow, or even a single finger. Clear grippers are an inconspicuous addition to door knobs. Grip handle measures 4" from end-to-end. Includes glow-in-the-dark inserts for additional safety in locating an exit during an emergency or finding the bathroom at night. With normal exposure to sunlight, the "glow" crystals will be visible for 6-plus hours. Recharging with sunlight will enable the "glow" crystals to continue working for the lifetime of your Glow-in-the-Dark Great Grips.