Folding Partitions and Components Thereof-Namely, Wood, Veneer [ and Fabric Covered ] Doors and Door Panels; [ Soundproof Doors and Door Panels; ] and Accessory Door Tracks and Trolleys [; Door Finishing Edging; Door Seals and Sealing Strips, Both Pneumatic and Mechanical; Partition-Forming Curtains, and Particularly Soundproof Curtains ]