Amazon.com: Prescott Plastics 1" Inch (25.4 mm) Round Plastic Hole Plugs, Inserts, Black End Caps for Metal Tubing, Hardware Plugs, Fences, Glide Protection from Chair Legs and Furniture - Pack of 10 :
Plastic End Cap, Threaded Male End Caps, Manufacturer, India
Made in USA Prescott Plastics 1/2" (12.7 mm) Round Vinyl End Cap, Black Rubber Cover for Metal Tubing, Fences, Glide Protection for Chairs and Furniture (10 Pack) - Amazon.com
Plastic End Caps 33.7mm – ProWeld
Made in USA Prescott Plastics 1 5/8" - 1.625" Inch Round Vinyl Plug Insert (4 Pack),
Budget End Caps, Cheap End Caps & Covers For Pipes - Vital Parts
Plastic Stopper 40x40mm End Cap Square Tube Black Plastic End Cap End Caps For Trampoline Furniture Legs 16pcs | Fruugo PT
Amazon.com: Prescott Plastics 1 1/4” (31.75 mm) Square Plastic Plug Insert, Black End Cap for Metal Tubing, Fences, Glide Protection for Chairs and Furnitures (10 Pack) : Industrial & Scientific