zvd stool swivel plate replacement square swivel mechanism rolling swivel boat seat swivel base mounting plate for bar stool, chair, table

size 147 mm x 147 mm 5.79 inch x 5.79 inch. 22 mm 0.87 inch high square plate, enough loading capacity about 250 pounds for bar stools, spin chairs, furniture and display stand. high quality the plate rotary swivel is made of galvanized steel, surface treated with zinc, corrosion and rust resistant,