Packing machine-based duty: monthly excise assessed by number of operating packing machines and declared retail price. Rules fix production capacity and monthly excise liability for notified chewing and unmanufactured tobacco by reference to the number of packing machines; a statutory table specifies pouches deemed produced per operating packing machine per month by retail sale price and lime tube content. Manufacturers must file Form 1 declarations of machines, planned operations and retail price denominations for verification and approval; monthly duty is computed by applying the notified rate to the number of operating packing machines, paid by the fifth day with reporting in Form 2, and changes in machines or production require supervised modification, sealing, or fresh declarations.