This set of spark plugs from Autolite is a great addition to your vehicle's ignition system. With a thread diameter of 14mm and hex size of 21mm, they are compatible with a range of models including Range Rover, LeMans, Sunbird and 560SEL. These vintage spark plugs have a copper core and are designed to work with gasoline-fueled engines with a voltage of 12V. The Autolite 66 spark plugs have a standard configuration and can be installed with a depth of .75 inches. They are performance parts that have interchangeable part numbers including 405, 3012, 7082, AG52, BPR4FS-11, and R45XLS. These spark plugs are made in the United States and have an OE/OEM part number of 88901006. Get your vehicle running smoothly with this set of Autolite 66 spark plugs.