Harley-Davidson Chrome Valve Cap Covers With Willy G Skull These Chrome finish Logo Valve Stem Caps add finishing touch to your wheels. Full color, highly detailed logos are permanent, fade- proof, waterproof and protected by a scratch-resistant polycarbonate coating as used in jet fighter canopies. Precision engineered and plated to show quality specifications. These are made of ABS plastic & do not interfere with TPMS Tire-pressure monitoring system. Logo Valve Caps fit any standard air valve cap stem.