If during checkout the buyer sends the currency to the payment address associated with another currency (for example Ethereum to Bitcoin), our system will not detect the payment and the merchant will not be able to access these funds and the buyer will be responsible in this case. 

Most wallets will flag you if you try to make an invalid payment, but we strongly recommend that you make sure to check the recipient's address before sending and the network you are using. 

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Using BTC payments Green Crypto Processing supports all types of output addresses such as: 

Legacy; SegWit; or Native SegWit 

Using Native SegWit addresses, the payment fee will be slightly reduced.