Omni-USDT is stored on the bitcoin address, so the type of fee to be paid for each transfer is bitcoin. The address is 1 or 3 at the beginning, for example, 1NTMakcgVwQpMdGxRQnFKyb3G1FAJysSfz. It is important that to successfully transfer Omni-USDT on the blockchain, there must be at least 0.0002 bitcoins in the address. At the same time, for each Omni-USDT transfer, a small amount of BTC transfer will be generated accordingly. In other words, when we made an Omni-USDT transfer on the blcokchain, two transfers "Omni-USDT and small BTC" actually took place.