This is the Suntech SEM-1417 automotive relay. A 12 volt, 30/40 amp, 5-pin SPDT (single pole, dual throw) relay. Sold as a single relay.

SPDT means it switches between two circuits rather than simply on and off, which is what most door lock, accessory and lighting work in a vehicle needs.

Specifications

• 12 volt
• 30/40 amp contacts
• 5 pin SPDT
• Sealed and waterproof
• Metal mounting tab

Suited to cars, light trucks, buses and heavy equipment running 12 volt systems. For a 24 volt vehicle, use the SEM-2417 instead.

Add the harness. A bare relay has spade terminals and nothing to plug into. The RH-200 relay harness is the matching socket with colour-coded leads already attached, and it turns a fiddly job into a quick one.