... diameter: 30/40/ 50mmPlate width: 38*38mm ; 40*40mmBrake: Nylon brake,without brakeFinish: Zinc-platedType: swivel Features:1.caster: swivel ... caster2.Nylon: anti-abrasion, rolling resistance,etc.3.finish: zinc-plated ... to resist bruise and corrosion4.brake:Nylon brake,without brake5.suitable scope: furniture,official dest,etc. ...