# Pre-fill (email, wallet, etc)

Need to pass in parameters to prefill email or wallet address? We support that!

Use the optional `walletAddress` to pre-fill the wallet address

Use the optional `email` to pre-fill the email

Example: 

```
  <WinterCheckout
    // Your projectId, will be the same in sandbox/production
    projectId={20}
    // When false we use tesntet & when true we use mainnet
    production={false}
    // This is a boolean that opens the widget when true
    showModal={showWinter}
    // Can pass in the customer's wallet address if you have it
    walletAddress='0x64EE4e11E0992D18C5986bA99F2d7DF8fc7A3dC3'
    // Can pass in the customer's email if you have it
    email="laila@usewinter.com"
    // Can pass in the mint quantity if the quantity is chosen before our modal is opened
    mintQuantity={5}
  />
```

If you've embedded the iframe directly, this example applies:&#x20;

<https://checkout.usewinter.com/?projectId=1&walletAddress=0xabcdefg&email=sean@awesome.com>


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