Return Policy – For any issues that you have please contact us first, we will try to assist you in a fair and equable manner. Except for “as is listings” we guarantee our tube against defects for mutual conductance, voltage, and leakage. If a tube is determined to be defective we will refund or replace with a “like tube” at our choosing.All claims shall be made within 14 days of shipment. Buyer is responsible for the cost of the return shipment. Unless a listing says that it is “guaranteed low noise, or guaranteed no microphonics” these conditions will not be considered defective. Non defective returns are subject a 25% restocking charge. Merchandise must be returned to us before any replacement, or credit is issued. Contact us for return address and RMA#, shipments received without an RMA numbers are subject to refusal. Once an RMA is issued we must receive a tracking number within 5 days, or the RMA will be canceled.