If you have received the incorrect spring size for your Irving slow rise shade, you can certainly exchange it for the correct 3/4" diameter spring if available. If the smaller diameter spring is not in stock, you are eligible to return the incorrect part for a refund. To facilitate your return, a return label has been provided and can be printed from your order account on our website or was sent via email. Please use this label to send the item back. If you have any further questions or need assistance with your exchange or return, please contact our customer service team for prompt support.