Guardian Industries Corp. v. United States

Maletz, Judge:

The importations in this case consist of flat pieces of tempered glass which are used in sliding glass patio doors. The glass pieces were produced in annealed form in the United States, sent to Canada for a heat treatment known as tempering and then returned to the United States. Upon their return in 1977 and 1978, they were classified by the government as tempered glass under item 544.31 of the Tariff Schedules of the United States (TSUS), and assessed duty of 11 percent ad valorem.1 Plaintiff claims that the tempering process is an alteration and that the imported merchandise…