19 CFR § 141.105 - Voluntary deposit of additional duties.
If either the importer of record or the actual owner whose declaration and superseding bond have been filed in accordance with § 141.20 desires, he may estimate, on the basis of information contained in the entry papers or obtainable from the Center director, the probable amount of unpaid duties which will be found due on the entire entry and deposit them in whole or in part with CBP, either at the port of entry or electronically. The deposit shall be tendered in writing in the following form in the number of copies required for the purposes of local administration, and an official receipt shall be given for the deposit:
Tender is hereby voluntarily made of $____________ as a supplemental deposit of estimated duties and taxes on ____________ entry No. ____________, dated ____________, in the name of ____________. Please provide an official receipt.