Pass out system for liquid gases allows removal without immediate duty, subject to PLA debit and strict recording safeguards. Manufacturers may remove liquid oxygen, nitrogen and other cryogenic gases without immediate payment of Central Excise under Rule 173G(1)(iv), subject to prior Board permission, a written application and undertaking, maintenance of sufficient PLA/RG balances, use of pre authenticated quadruplicate Pass Out Documents, customer wise recording of deliveries, maintenance of a special register for deliveries/returns/losses, subsequent invoicing and debit of duty entries dated to dispatch, payment of duty on transit or storage losses at the highest effective rate, and compliance with Commissioner imposed safeguards.