The Weatherproof Eyelet Lead is for use with OptiMate battery chargers, it is suitable for use with the Optimate 2 (not the pre-2000 model, Optimate 3+ abd Optimate 4 models. This version is SAE Compatible and enables a permanent connection to the battery. It features a rubber cover which fits over the 2-pin connector keeping the electrical connections dry and corrosion free.If you own more than one vehicle, these leads allows the ability to fit one to each battery; this way one OptiMate can be used with several vehicles on a rotational basis very simply and quickly.Simply connect the ring terminals to your battery and the 2-pin connector will always be available to connect your OptiMate, ideal for hard to access batteries