Penrite Shelsley Medium - For pre and post-war vehicles before 1950Penrite Shelsley MEDIUM is a premium Mineral, high Zinc, very low detergent, 25W-70 engine oil designed specifically for petrol, kerosene and Diesel fuelled Vintage, pre-war and post war vehicles manufactured to 1950. It features a DOUBLE LAYER of engine wear protection with high zinc and increased operating temperature viscosity over Monograde oils. Have a vintage project or retro cruiser? Penrite Classic is a range of engine oil which has been formulated with the specific requirements of classic, veteran and vintage vehicles in mind. Penrite Classic utilises unique technology including optimised zinc levels and modern additives to protect and enhance the longevity of older, unique engines including a tacky additive which assists with lubrication when the vehicle is in storage and not in use to protect from aggressive wear when starting up. The Penrite Classic range includes engine oils for pre-90's vehicles, pre-WWII vehicles and even pre-1920's vehicles and even application-specific engine oil for classic Minis and air-cooled Volkswagens with special formulations designed to protect these vehicles. Penrite Classic contains extra protection to inhibit internal corrosion and deterioration of engine parts when the vehicle is not in use for extended periods of time.