PKG (4) 6" Dia. Hollow Black Plastic Wagon Wheels BURN RUBBERMAID These hard, black-plastic wheels are from Rubbermaid, made, we think, for wheelie garbage bins available to you for to add wheels to whatever you want to roll. Measure 6" dia x 1-3/4" thick with a 3/8" axle bore standing off 5/8" on one side and countersunk 1/4" on the other. They're hollow and very lightweight, so they're ideal for homemade kiddie vehicles or wagons.