A transaction fee is a charge by the payment processor (PayPal) when you make an online payment. This fee is collected by PayPal and is non-refundable. Therefore, if you cancel an order, you will receive a full refund for the order amount, but not the transaction fee.
We collect a 2.35% transaction fee to cover part of PayPal's actual fee, which is 2.9% plus a fixed amount (usually $0.30). During a refund, the non-refundable transaction fee is 2.9% plus the fixed amount, not 2.35%.