7 U.S.C. § 621

Machinery belting processed from cotton; exemption from tax

The provisions of section 616 of this title , shall not apply to articles of machinery belting processed wholly or in chief value from cotton, if such processing was completed prior to January 1, 1930 .

( June 26, 1934, ch. 753, § 1 , 48 Stat. 1223 .)