# Vault mechanics

### Leveraged Vault Attributes

* **Primary currency:** Every vault will involve borrowing one currency type from Notional. The vault itself might interact with multiple currencies and assets, but the debt that the user takes out and the value of a vaultShare will be denominated in the primary currency.

* **Secondary currency:** Some, but not all, vaults will involve borrowing a second currency type from Notional in addition to the primary currency. An example of a two-currency vault would be a vault that borrows ETH and USDC from Notional to deposit as liquidity into the ETH/USDC pool on Uniswap V2.

* **Max leverage ratio:** Every vault will specify the maximum amount of leverage that a user can obtain. If the value of the user's assets <mark style="color:green;">exceeds</mark> the limit and they breach this ratio, they can be liquidated.

* **Minimum borrow size:** Users must maintain a minimum debt size to use Notional's levered vaults. Minimum debt sizes ensure that liquidators have a sufficient financial incentive to liquidate levered vault positions in adverse market conditions.

* **Max capacity:** Levered vaults maintain a capped borrowing capacity that is a function of the risk of the strategy and the strategy's overall capacity.

* **Vault fee:** Users pay a fee to use a leveraged vault that varies by vault depending on the riskiness and potential profitability of the strategy. The fee is assessed on the interest rate that the user pays on their debt when they enter the vault and it is split between nToken holders and the protocol's reserve.

* [ ] What happens when you enter

* [ ] What happens when you exit

* [ ] What happens when you roll
