Polaroid Pro Studio 3 Professional Caster Wheels for Light Stands with 22mm Tubular Leg Ends Three Professional Caster Wheels Will Fit Any 22mm Diameter Leg Endings Heavy Duty Construction Step On Locks Allow You To Easily Keep Your Equipment In Place Will Fit On The Following Polaroid Light Stands (PLSEREFSTAND, PLSEBGKIT, PLSELIGHTSTAND) Plus Any Light Stand That Has A 22mm Leg Ending