Check the listing for details. The Lewis Engine Co. Airplane VINTAGE Thermometer Tester Weston 81TT3 1948. Condition: Used. Listed at 72.00 USD. This vintage thermometer tester from The Lewis Engine Co. is a must-have for aviation enthusiasts. It is compatible with the Weston 81TT3 model and was manufactured in 1948. The brand is well-known for its quality products, and this tester is no exception. It is perfect for measuring the temperature of an engine and determining its health. The product has been well-maintained and is in excellent working order. It would make a great addition to any collection of aviation parts and accessories. The manufacturer part number is 81TT3, and it is categorized under Indicators, Avionics, Aviation Parts & Accessories, and Parts & Accessories on eBay Motors. Don't miss out on the opportunity to own a piece of aviation history with this vintage Lewis Engine Co. thermometer tester.