Sealey 6" Orbital Sander Backing Pad For Sanding Discs. Model: PTC/150SA. Features on the item: Sealey professional dual action random orbital backing pad Suitable for air and electric tools fitted with 5/16”UNF thread Diameter-Thread: Ø150mm (6") x 5/16”UNF x 24 threads Max Speed 10,000 rpm Suitabi..