6 METALLIC SEALED SLIDING DOORS AND HANGER DEVICES, NAMELY, GUIDE RAILS, SECTIONS, IRON FITTINGS, ANGLE IRON, RAIL WHEEL; COMPONENTS OF ROLLING, NAMELY, ROLLINGS, ROLLERBEARINGS, NEEDLE BEARINGS, BALL BEARINGS (OR BALLS, NEEDLES AND ROLLERS FOR BEARING), SLIDE BEARINGS; SLIDINGS, RAMPS, SUPPORTS, OSCILLATORY ARMS