Sierra MP39520 Push-Pull Switch, On-Off SPST, Solid Brass, 3/8 Inch Mounting Bushing

The Sierra MP39520 is a push-pull toggle switch built for on-off SPST switching in 12-volt marine electrical circuits. Constructed of solid brass, the switch is designed to hold up in the corrosion-prone environment of a boat's helm or accessory panel, where cheaper plastic-bodied switches tend to fail. Operation is simple: pull the knob to turn the connected circuit on, push it in to turn it off, making it a natural fit for bilge pumps, lights, blowers, horns, and other 12-volt accessories that call for a straightforward manual switch rather than a rocker or toggle.

The switch mounts through a 3/8 inch bushing and is sized to fit panels up to 1 inch thick, so it can be installed in most dash, console, or accessory panel cutouts without needing a custom-drilled hole. It terminates in two screw terminals for a secure, serviceable wiring connection, and the knob itself is a chrome-plated plastic finish that resists fading and wear from sun and spray. Rated for 15 amps at 12 VDC, the MP39520 is sized for typical low-draw marine accessory circuits.

Specifications

• Brand: Sierra
• Manufacturer Part Number: MP39520
• Switch Type: Push-Pull, Off-On SPST
• Amperage Rating: 15 amps at 12 VDC
• Construction: Solid brass body
• Knob Finish: Chrome-plated plastic
• Terminals: Two screw terminals
• Mounting Bushing Size: 3/8 inch
• Panel Thickness Fit: Up to 1 inch
• Product Dimensions: 3.18 x 1.75 x 6.81 inches
• Weight: 0.15 pounds
• UPC: 808282368067

Fitment

This is a universal 12-volt panel-mount switch; no make, model, or year-specific fitment applies.

Replaces (OEM)

No OEM cross-reference numbers apply to this part.

Frequently Asked Questions

Is the Sierra MP39520 an on-off switch or does it have multiple positions? The Sierra MP39520 is a single-pole, single-throw (SPST) switch with two positions: off and on. Pulling the knob turns the circuit on, and pushing it in turns it off.

What amperage can the MP39520 handle? It is rated for 15 amps at 12 VDC, which covers typical marine accessory circuits like bilge pumps, lights, blowers, and horns.

What material is the Sierra MP39520 switch made of? The switch body is solid brass, chosen for its resistance to corrosion in a marine environment, with a chrome-plated plastic knob.

How thick of a panel does the MP39520 fit? The Sierra MP39520 is designed to fit panels up to 1 inch thick, using its 3/8 inch mounting bushing.

What size mounting hole does the MP39520 need? It uses a 3/8 inch mounting bushing, so the panel cutout should be sized to accept that bushing diameter.

How is the Sierra MP39520 wired? It terminates in two screw terminals, allowing wires to be secured directly under the terminal screws rather than requiring soldered or crimped connections.

How much does the MP39520 weigh? The Sierra MP39520 weighs 0.15 pounds.

What are the physical dimensions of the MP39520 switch? The switch measures 3.18 x 1.75 x 6.81 inches.

Does the MP39520 come in a bulk package option? Yes, the same switch design is available in a bulk carton of 100 pieces under Sierra part number MP39522, while the MP39520 is the standard single-unit package.

Is the Sierra MP39520 suitable for use on a boat dashboard? Yes, its push-pull operation, brass construction, and panel mounting design make it well suited to boat dash or accessory panel installations.

What is included when you buy the MP39520? The Sierra MP39520 ships as a complete push-pull switch assembly with mounting bushing and knob, ready to wire to its two screw terminals.