Captain O-Ring - Rubber Oring Keyboard Switch Dampeners/Sound Reducers Red [40A-L 0.2mm] Reduction (135 pcs w/ screen cloth) 0.2mm travel reduction allows for sound reduction with minimal change in feel Significantly reduces keyboard sound level by preventing "bottoming out" of keys Minimizes finger fatigue by shortening travel and lessening impact High quality EPDM rubber resists cracking and tearing Includes 135 O-Rings & Captain O-Ring Screen Cleaning Microfiber Cloth