This is one of the two forms required for the entry of articles which are returned after having been exported for repairs or alterations using Harmonized Tariff Schedule (HTS) 9802.00.40 or 9802.00.50.
The Repaired Goods Declaration for U.S. Imports is completed by the foreign party who repaired the goods, and must show a value for parts and labor, even if a no charge.
The other form is the Owner, importer repair declaration (Declaration by the owner, importer, consignee, or agent), which is prepared by someone with knowledge of the pertinent facts to the return and repair/alterations.
They are required per 19 CFR § 10.8 Articles exported for repairs or alterations. These two forms are also used to obtain USMCA treatment to goods repaired or altered in Canada or Mexico (see 19 CFR § 182.112 Goods re-entered after repair or alteration in Canada or Mexico).