8716909000 under HS Code TRAILERS AND SEMI-TRAILERS; OTHER VEHICLES, NOT MECHANICALLY PROPELLED; PARTS THEREOF PARTS OTHER, 8716901000 under HS Code TRAILERS AND SEMI-TRAILERS; OTHER VEHICLES, NOT MECHANICALLY PROPELLED; PARTS THEREOF PARTS : PARTS AND ACCESSORIES OF TRAILERS, and 5909001000 under HS Code TEXTILE HOSE PIPING AND SIMILAR TEXTILE TUBING, WITH OR WITHOUT LINING, ARMOUR OR ACCESSORIES OF OTHER MATERIALS - TEXTILE HOSE PIPING AND SIMILAR TEXTILE TUBING, WITH OR WITHOUT LINING, ARMOUR OR ACCESSORIES OF OTHER MATERIALS : OF COTTON were the top imported HS Codes by NPO OIL AND GAS ENGINEERING AND SPECIAL AUTOMOTIVE ENGINEERING LLC in 2021.