Sea-Dog 420118-1 Illuminating Toggle Switch, SPDT On/Off/On, 15 Amp 12 Volt

The Sea-Dog 420118-1 is an illuminating toggle switch built for marine electrical panels where visibility and water resistance matter. It uses an SPDT (single pole, double throw) circuit with an On/Off/On action, giving it three switch positions for controlling two separate circuits from one switch. The toggle lights up red when the switch is in the ON position, making it easy to confirm at a glance that a circuit is live, even in low-light conditions at the helm.

Construction is stamped brass and injection molded nylon, with a polycarbonate toggle lever. A locking ring and lever seal help resist water penetration, which is important for switches mounted on an open helm or in a cockpit where spray and moisture are a constant. The switch terminates in four 1/4 inch spade (quick connect) blade terminals, so wiring in or replacing an existing switch is straightforward without soldering.

This switch is rated 15 Amps at 12 Volts DC. It is designed to fit panels up to 1/4 inch thick and requires a 15/32 inch mounting hole. Its compact panel footprint and standard spade terminals make it a straightforward drop-in for boat dash panels, helm stations, and accessory switch panels that call for an illuminated SPDT On/Off/On toggle switch.

Specifications

• Brand: Sea-Dog
• Manufacturer Part Number: 420118-1
• Circuit Type: SPDT (Single Pole, Double Throw)
• Switch Action: On/Off/On
• Terminals: 4 Blades (1/4 inch spade, quick connect)
• Amperage: 15 Amps
• Voltage: 12 Volts DC
• Illumination: Illuminates red in the ON position
• Mounting Hole Size: 15/32 inch
• Maximum Panel Thickness: 1/4 inch
• Dimension A: 3/8 inch
• Dimension B: 1/2 inch
• Material: Stamped brass, injection molded nylon, polycarbonate toggle
• Mounting Type: Panel mount
• Weight: 0.062 pounds

Frequently Asked Questions

What does SPDT On/Off/On mean on this switch? SPDT stands for single pole, double throw, meaning the Sea-Dog 420118-1 has three positions (On/Off/On) and can direct power to two different circuits from a single switch, one circuit at a time.

Does the toggle light up? Yes, the 420118-1 illuminates red when the toggle is switched to the ON position, so you can see its status at a glance on a panel.

What size mounting hole does this switch need? The Sea-Dog 420118-1 requires a 15/32 inch mounting hole and fits panels up to 1/4 inch thick.

What amperage and voltage is this switch rated for? It is rated 15 Amps at 12 Volts DC, suitable for typical marine 12 volt accessory and lighting circuits.

What type of terminals does the 420118-1 use? It has 4 blade terminals using 1/4 inch spade (quick connect) style connections, allowing wiring without soldering.

Is this switch water resistant? The switch includes a locking ring and lever seal designed to resist water penetration, which helps it hold up in exposed marine helm and cockpit locations.

What is the toggle switch made of? The Sea-Dog 420118-1 is constructed of stamped brass and injection molded nylon, with a polycarbonate toggle lever.

How much does this switch weigh? The 420118-1 toggle switch weighs 0.062 pounds.

How is the 420118-1 different from the 420118 non-illuminating version? The 420118-1 is the illuminating variant of the SPDT On/Off/On toggle switch line, lighting up red when in the ON position, while sharing the same 15 Amp, 12 Volt, 4-blade terminal specifications as other switches in the family.

What size are the dimensions A and B on this switch? The Sea-Dog 420118-1 has a Dimension A of 3/8 inch and a Dimension B of 1/2 inch.

Can this switch be used to control two separate circuits? Yes, because it is SPDT with an On/Off/On action, the 420118-1 can switch power between two different circuits depending on toggle position.