When customers purchase an NFT using our Shopify app, and you're covering gas costs, your merchant wallet is used to pay the gas costs for minting. On the Polygon chain this cost is covered by Verisart. However, on Ethereum you need to top up your merchant wallet yourself with ETH to cover costs.

To ensure that you don't spend too much, you can set a gas limit (in GWEI). If the current gas price is greater than this amount, mints will be held until the gas price falls below this value.

The benefit of this is that you can ensure you can set a limit on your minting costs. Please note, that your customers will not receive their NFT until gas prices fall below your limit and their NFT will appear is "pending" in their dashboard.

To set a limit, use the Gas price limit panel in the settings part of the Shopify App:
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Note that the price shown above is the worst case - you are likely to spend less than this depending on gas prices. The Estimated costs panel (just above the Gas price limit panel) shows you the estimated cost based on current gas prices.