Current possessors of bump-stock-type devices must divest themselves of possession before the effective date of the final rule.
One option is to destroy the device, and the final rule identifies possible methods of destruction, to include completely melting, shredding, or crushing the device. Any method of destruction must render the device incapable of being readily restored to function.
Current possessors also have the option to abandon bump-stock-type devices at the nearest ATF office. ATF advises that it is best to make an appointment beforehand with the nearest ATF office. Please consult the Local ATF Offices webpage for office contact information.