9903.81.44

HS 编码 9903.81.44（）在美国税则中对应"Mechanical tubing (provided for in subheading 7304.31.30, 7304.31.60 (except for statistical reporting number 7304.31.6010), 7304.39.00 (except for statistical reporting number 7304.39.0002, 7304.39.0004, 7304.39.0006, 7304.39.0008, 7304.39.0016, 7304.39.0020, 7304.39.0024, 7304.39.0036, 7304.39.0048, 7304.39.0062, 7304.39.0076 or 7304.39.0080), 7304.51.10, 7304.51.50 (except for statistical reporting number 7304.51.5005, 7304.51.5015 or 7304.51.5045), 7304.59.10, 7304.59.60, 7304.59.80 (except for statistical reporting number 7304.59.8010, 7304.59.8015, 7304.59.8030, 7304.59.8045, 7304.59.8060 or 7304.59.8080), 7304.90.50, 7304.90.70, 7306.30.10, 7306.30.50 (except for statistical reporting number 7306.30.5010, 7306.30.5026, 7306.30.5027, 7306.30.5028, 7306.30.5031, 7306.30.5033, 7306.30.5041, 7306.30.5043, 7306.30.5056, 7306.30.5057, 7306.30.5085 or 7306.30.5090), 7306.50.10, 7306.50.50 (except for statistical reporting number 7306.50.5010), 7306.61.50, 7306.61.70 (except for statistical reporting number 7306.61.7030), 7306.69.50 or 7306.69.70 (except for statistical reporting number 7306.69.7030))"。美国海关对该编码商品征收最惠国税率 (MFN) Free。