# Vault post-deployment operations
## Underlying asset approval
To enable user withdrawals, the custodial wallet (`safe` parameter) must infinite approve the vault address to spend `underlying`. For example, if the underlying is USDC, then as the safe you should approve the Vault to spend your USDC.
Call the following function on the underlying asset contract:
```solidity
approve(address spender, uint256 value)
```
* **`spender (address)`:**\
The deployed **vault address**. This is the address that will be allowed to move the tokens from the curation address.
* **`value (uint256)`:**\
The approval amount. To avoid repeated approvals, you can do an infinite allowance. Use the following constant value:
```
115792089237316195423570985008687907853269984665640564039457584007913129639935
```
{% hint style="danger" %}
Without this approval, the vault will not be able to process user withdrawals.
{% endhint %}
***
## Verify your vault on Etherscan
### Identify your vault as a proxy
Before interacting with your vault, you must confirm that it is a proxy contract.
#### Steps to verify the proxy
1. **Access Your Vault Contract**
* Open your Vault’s contract page on the relevant block explorer (e.g., Etherscan, Arbiscan, etc..).
2. **Navigate to the Contract Tab**
* Click on the **`Contract`** tab.
3. **Click “Is this a proxy?”**
* Scroll to the top right of section, click on the **“Is this a proxy?”** button and then on the "**Verify**" button.
4. **Confirm Proxy Verification**
* If verified, the explorer will display the interaction with the proxy logic.
Once your vault is confirmed as a proxy, you will be able to access the **Read** and **Write** functions of the deployed vault contract.
