6X4 Mullard used rectifier tube. Manufactured in Gt Britain with Blackburn codes YY1/B9H. The tube tests at 100%/100%. The minimum is 68%. The tube will be properly packed for safe shipment, and I will pay insured USPS postage with tracking number in the US. Same business day shipping. International shipping through eBay Global Shipping at actual postage cost with actual selling price on the customs documents. 7 ounces packed weight for international shipment.