In exchange for the stock the grantor takes back a promissory note, again bearing a government-specified rate of interest (currently less than 1% for a nine-year note) that locks the value of the stock in at the time of the transfer.
With a GRAT, the owner of a company can transfer stock in the firm into a trust for the benefit of heirs and take back an annuity representing the current value of that stock plus a government-specified interest rate, currently 1%.
It allows certain specified goods to be imported for processing or incorporation into finished products at the rate of Customs duty that would be applicable to the finished product, that is, zero, instead of the rate for the imported goods.