Fuel Pump Question

So Inline tube is taking back the 3/8 and exchanging it for the 5/16. They sent me a FedEx return label and said if I order the 5/16 then they will only charge a 10% restocking fee as opposed to the normal 20%. It is worth it to me since it was my mistake ordering the 3/8 instead of the 5/16. Lesson learned for sure here. Pay attention.