Amazon.com: Prescott Plastics 0.875 Inch Square Plastic Plug Insert, Black End Cap for Metal Tubing, Fence, Glide Insert for Pipe Post, Chairs and Furnitures (10 Pack) : Industrial & Scientific
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Prescott Plastics 1 1/2” (38.1 mm) Square Plastic Plug Insert, Black End Cap for Metal Tubing, Fences, Glide Protection for Chairs and Furnitures (4 Pack) - - Amazon.com