Sealey Auto Electronics Protection Device 24V PROSAF/24Housed in tough composite case, this unit is designed to prevent damaging voltage spikes and surges reaching delicate vehicle electronics. Clips across the battery terminals and permits processes such as welding and plasma cutting to be carried out without the danger of damaging the vehicles onboard electronics. Fitting recommended before any routine workshop maintenance. Shows red light for fault. Fitted with heavy duty, fully insulated battery