Sierra Rotary Selector Switch MP78860, 4-Position Off-On1-On2-On1&2, Switch Only

The Sierra MP78860 is a 4-position rotary selector switch built for marine electrical panels that need to control two separate circuits from a single switch. The rotary knob turret cycles through Off, On 1, On 2, and On 1 & 2, letting an operator run either circuit independently or activate both at the same time without needing two separate switches on the panel. This makes it a practical choice for dual-circuit setups such as split lighting banks, dual pump controls, or other two-circuit accessory arrangements where a single panel opening is preferred over mounting two switches.

This is a switch-only unit; it does not include a knob, so an existing knob or a separately purchased knob is required to operate it once installed. The compact design is intended for standard marine switch panel cutouts, keeping panel layouts clean while still providing full control over both connected circuits. At 0.14 pounds, it is a lightweight, low-profile component suited for retrofit or new-build panel work.

Specifications

• Brand: Sierra
• Manufacturer Part Number: MP78860
• Product Name: Switch Rotary Off-On1-On2-On1&2
• Switch Positions: Off, On 1, On 2, On 1 & 2 (4 positions)
• Configuration: Switch only, no knob included
• Category: Switches & Panels
• Weight: 0.14 pounds
• UPC: 808282368333

Frequently Asked Questions

What are the switch positions on the Sierra MP78860? The MP78860 is a 4-position rotary switch with Off, On 1, On 2, and On 1 & 2 settings, allowing either circuit to be run separately or both circuits to be run together.

Does the MP78860 come with a knob? No, the Sierra MP78860 is a switch-only unit and does not include a knob; a compatible knob must be installed separately to operate it.

What is the MP78860 used for? It functions as a rotary selector switch for controlling two separate marine electrical circuits from one panel position, useful for setups like dual lighting banks or dual pump controls.

How much does the MP78860 weigh? The Sierra MP78860 rotary switch weighs 0.14 pounds.

Can I run both circuits at the same time with this switch? Yes, the On 1 & 2 position on the MP78860 activates both connected circuits simultaneously, in addition to the independent On 1 and On 2 positions.

Is the MP78860 an On-Off-On style switch or something different? It is a 4-position rotary switch (Off, On 1, On 2, On 1 & 2), which offers an additional combined-circuit position beyond a standard 2-position On-Off-On switch.

What is the UPC for the Sierra MP78860? The UPC for the Sierra MP78860 rotary switch is 808282368333.

Is the MP78860 genuine Sierra hardware? Yes, MP78860 is the genuine Sierra manufacturer part number for this rotary selector switch.

What comes in the box with the MP78860? The MP78860 ships as the switch mechanism only; since it is a switch-only unit with no knob, the knob is not included and must be sourced separately.

What category of marine part is the MP78860? Sierra lists the MP78860 under Switches & Panels, making it suited for installation in a marine switch panel.