MouseBlocker 12V Ultrasonic Under-Hood Rodent Deterrent — Compact Weatherproof Continuous 85 dB Protection

MouseBlocker 12V Ultrasonic Under Hood Mouse and Rodent Deterrent is a compact, battery-powered device that emits targeted ultrasonic sound to discourage rodents from nesting and chewing in vehicle engine bays.

Rodents in engine compartments can chew wiring harnesses, hoses and plastic components, causing expensive repairs and inconvenient breakdowns. The MouseBlocker is designed for direct 12V installation under the hood so it runs off the vehicle battery, tolerates extreme temperatures and moisture, and operates continuously without replacing batteries. It aims to make the engine area uncomfortable for rodents by emitting a focused, high-decibel ultrasonic signal chosen to mimic harsh mechanical noises that pests avoid.

How does the MouseBlocker prevent rodents from nesting under my hood?

The unit produces a concentrated ultrasonic frequency at about 85 decibels selected to be unpleasant to mice and similar pests. When mounted in the engine bay, the sound interferes with the animals' comfort in that space, discouraging them from building nests or gnawing on components.

• Emits targeted ultrasonic tones designed for small mammals’ hearing range
• 85 dB output creates a continuous deterrent effect
• Placement in engine compartment maximizes coverage of wiring and hoses
• Does not rely on chemicals, sticky traps, or bait

Is installation difficult and will it drain my vehicle battery?

Installation is straightforward: the MouseBlocker connects to your vehicle’s 12V battery with two wires and mounts under the hood. It is engineered to draw only about 0.1 watts, so it runs continuously without significantly affecting battery life on a properly maintained vehicle.

• Simple two-wire hookup directly to 12V battery terminals
• Compact size roughly equal to a deck of cards for convenient mounting
• Ultra-low 0.1 W power draw minimizes impact on battery
• Runs automatically whenever the vehicle battery is connected

Will the MouseBlocker survive extreme temperatures and moisture?

The unit is built for under-hood conditions, capable of withstanding both high engine-bay heat and subzero cold. It is also unaffected by damp environments, making it suitable for a wide range of vehicles and climates.

• Designed for high under-hood temperatures without failure
• Operates reliably in very low temperatures, suitable for cold climates
• Resistant to typical engine-bay moisture and humidity
• Durable housing sized for tight engine compartments

What vehicles and situations is this device intended for?

The MouseBlocker works wherever a stable 12V power source is available, including cars, trucks, motorcycles, ATVs, snowmobiles, RVs, boats with 12V systems, farm equipment and more. Its small footprint and rugged design make it practical for dealers, repair shops and individual owners who want continuous protection without maintenance.

• Fits cars, trucks, motorcycles, snowmobiles, RVs, and boats with 12V
• Commonly used by dealerships and independent repair shops
• Protection for stored or seasonal vehicles prone to rodent damage
• Non-toxic deterrent—suitable around stored equipment and garages

Who is this for: The MouseBlocker 12V Ultrasonic Under Hood Deterrent is aimed at vehicle owners, fleet managers, dealerships and repair shops that need a continuous, low-maintenance way to reduce rodent-related damage. It suits anyone who wants a compact, energy-efficient device that installs easily, runs off the vehicle battery, and is built to tolerate typical engine-bay conditions. If you own or service vehicles kept in garages, barns or outdoors where mice and rats are a recurring problem, this unit provides a hands-off layer of protection to help reduce wiring, hose and component damage without using traps or poisons.

Key features include:

• Direct 12V connection—no disposable batteries
• Compact, weather-tolerant housing for engine compartments
• 85 dB ultrasonic output tailored to deter rodents
• Extremely low power consumption (about 0.1 W)
• Trusted by dealers and repair shops across North America