"Gas Tank" is one of Ambire’s standout features. It significantly improves the cross-chain UX, by allowing you to use your Gas Tank balance to pay gas fees on any of the natively supported EVM networks.
Not only that, but you can also top it up with various tokens on any of the natively supported networks.
Shortly speaking, it allows you to use an ERC-20 token from network "A" to pay your gas fees on network "B," regardless of having native tokens or even any balance on network "B".
How you can use the Gas Tank?
Once you have assets in your Gas Tank, you will see it among the options under the "Gas fee estimation" on the transaction window:
If the balance of your Gas Tank covers the transaction fee, you will be able to select it as a payment option.
Where the Gas Tank balance comes from
Your gas tank receives assets in two ways.
1) Automatically, via so-called "Cashback". When you request a transaction, you are presented with an estimated fee, based on the gas rates at the time of creating the transaction. In many cases, that estimation is different from the real fee paid in the end to the network, when the transaction is mined. Better part of this difference is automatically returned to the user's Gas Tank and we refer to it as "Cashback".
2) Manually, by sending funds from your portfolio to your Gas Tank. You can top it up with various tokens (see the list here) via any of the natively supported EVM networks.
You can find more details on how to top your Gas Tank from the extension here, and from web wallet here.
How much fees does the Gas Tank save?
The Gas Tank works like a pre-pay mechanism. It credit the Relayer (a back end service) in advance through one deposit, instead of depositing (which requires additional fee) with each transaction.
When you select Gas Tank as a payment option for your transaction, you are won't be charged with those additional gas fees for each transaction to the Relayer, since you will already have tokens there. This means you will pay less for every new transaction that needs to be executed, while the Gas Tank feature is active, therefore saving significantly over time. We refer to these amounts as "Saved".
You can see the total amount of "Saved" and "Cashback" funds by clicking on the "Gas Tank" at your dashboard:
How much gas fees will be saved from the Gas Tank, and how much will be returned in cashback depends on many factors, like how busy the network is at this moment, what is the trend of the gas fees (going up or down) and more. This is the reason why the "Saved" and "Cashback" amounts are different for each transaction.
FAQ
- Can you withdraw from the Gas Tank?
You will not be able to withdraw from the gas tank. You would need to use up the funds you deposit there.
- What is the "Relayer"?
The Relayer is a back end service, which is responsible for broadcasting transactions to the network. It exists because of the gas abstraction mechanism which allows users to pay transaction fees in any token and enables the Relayer to automatically manage gas fees. Therefore, the Relayer saves Ambire Wallet users a lot of fees in total, but a small additional fee is paid whenever it is used.