28mm x 28mm Plastic Ribbed Square End Caps Tube Inserts Black 24 Pcs Product Mame : SquareTube Insert;Top Size : 28 x 28mm / 1.1" x 1.1"(L*W) Thread Size : 27 x 27mm / 1.06" x 1.06"(L*W);Overall Height : 17mm / 0.67" Material : Plastic;Color : Black Net Weight : 87g Package Content : 24 x SquareTube Insert