Pro-Tect Nylon Washer for 1/4 in. Cap and 1/4 in. Hex-Head Blue Tap Concrete Screw (100 per Pack) PT4W100 - The Home Depot
Jwodo Toilet Bolt Caps, 4Packs Universal Plastic Round Push-On Toilet Bowl Caps Covers, with Extra Washers for Easy installation, 1.43 Inch Height, White Color - Amazon.com
HOLT Marine Prepack Plastic Screw Cap Covers and Washers (PPD/PPE) | eBay
Hydropool.com | SR Smith Item 63-727-1040 - Washer Assembly, Recessed Plastic w/Cover, White
Amazon.com: Hat Washers, Cap Washers for Washing Machine, Hat Cleaning Shaper Protector Fit for Adult and Kid's Baseball Caps, White (1 Pack) : Home & Kitchen