Answering the question, these are reliable, mechanically driven braking systems designed to help control a towed vehicle when RVing. They’re best for RV owners and travel-trailers who want a straightforward, proven setup that doesn’t rely on complex electronics. The top picks include purely mechanical options, hidden installs, and easy-to-use emergency systems. This guide highlights five models, what they’re best for, and practical trade-offs to help you choose.
Summary at-a-glance: the table below compares key points to help you decide quickly.
| Product | Best For | Key Benefit | Notable Limitation |
|---|---|---|---|
| Simple, reliable towing setups | Purely mechanical with proportional braking | May require careful installation for some vehicles | |
| Compact, low-profile installs | Braking system designed to stay installed with modest footprint | Limited details available in supplied features | |
| Under-seat installs, space-saving | Energizes factory brakes for consistent stopping | Requires mounting under interior panels or trunk space | |
| Non-electronic backup during emergencies | Mechanical brake activation via pedal cable | Non-electronic design may lack advanced diagnostics | |
| All-around reliability with monitoring | Proportional braking with LED monitor | Requires proper setup to ensure compatibility with brakes |
NSA RV ReadyBrake Towed Vehicle Supplemental Surge Brake System

- Type: Proportional, Mechanical surge brake
- Fit: Universal hitch-mounted tow bar
- Construction: Purely mechanical system not relying on electronics
- Installation: 2026 cable routing streamlines setup; no firewall drilling required
Best for: RV owners who want a simple, reliable mechanical brake link with proportional response. It’s well-suited for towed vehicles across a wide range of hitches.
Why selected: It emphasizes mechanical reliability and straightforward installation, reducing potential electronic failure points.
Caution: Some installs may require precise alignment to ensure proportional braking, especially with unusual hitch configurations.
Demco Stay-in-Play Duo Braking System

- Product Type: Braking system for towed vehicles
- Package Details: Moderate dimensions and weight suitable for many setups
- Compatibility: Designed for use with common auto accessories
Best for: Travelers seeking a discreet, low-profile braking solution with straightforward mounting.
Why selected: Its compact design helps keep interior space open while delivering proportional braking behavior.
Caution: Limited feature details in the brief product data may require confirming compatibility with your specific vehicle and tow bar.
Roadmaster Invisibrake Braking System

- Compatibility: Fits towed vehicles with vacuum-powered brakes
- Mechanism: Energizes factory brakes, providing consistent power as when driving
- Size: Small footprint (8″ x 8″ x 2″) for flexible mounting
Best for: Those who want a hidden install that preserves interior space while delivering familiar braking performance.
Why selected: The system leverages the vehicle’s power brakes to create identical stopping feel when towing.
Caution: Installation may require mounting under seats or panels, which could complicate access for some owners.
Flat Towing Emergency Braking System (Camoo)

- Type: Non-electronic emergency brake pedal cable system
- Use: Specifically designed for RV flat towing emergencies
- Function: Mechanical backup that activates the brake pedal during tow separation
Best for: RV flat-tow configurations needing a simple, dependable backup in emergencies.
Why selected: Its purely mechanical design offers a reliable fail-safe without reliance on power or electronics.
Caution: Non-electronic systems may lack some advanced diagnostics or monitoring options found in electronic setups.
Roadmaster 9400 Even Brake with LED Monitor

- Compatibility: Fits any towed vehicle
- Braking: Proportional braking with Even Brake technology
- Monitor: LED monitor for braking activity and safety
Best for: RVers who want a complete system with a visual indicator to monitor braking events.
Why selected: The combination of proportional braking and a monitoring LED helps ensure braking coverage while towing.
Caution: Correct alignment and setup are essential to avoid under- or over-braking on certain vehicles.
Buying Guide: Key Considerations For Selecting A Towed Vehicle Braking System
- Decide between purely mechanical (no electronics), hybrid, or fully electronic systems. Mechanical systems tend to be simpler and more rugged; electronic options often provide enhanced diagnostics and easier tuning.
- Verify that the system supports your tow vehicle’s braking power, hitch type, and whether your towed vehicle uses vacuum brakes, hydraulic brakes, or electric braking signals.
- Consider space where the device will mount. Under-seat or trunk installs save interior space but may require more concealment work.
- Systems that mirror your motorhome’s braking depth can provide smoother, safer stops compared with non-proportional designs.
- Some setups include breakaway compatibility or LED monitoring. Evaluate whether these features fit your risk tolerance and maintenance routine.
- If you tow with multiple vehicles, a portable solution that transfers easily can be beneficial. Mechanical units typically require less maintenance than electronic ones.
- Some products require professional installation, while others are DIY-friendly with basic tools. Assess your comfort with vehicle systems before purchase.
FAQ
- What is a supplemental braking system for a towed vehicle? It is an add-on device that helps control the brakes of a vehicle being towed behind an RV, enhancing safety during deceleration.
- Which type is easiest to install? Purely mechanical systems with universal fit options tend to be easiest for DIY installation and offer straightforward maintenance.
- Do these systems require electronics? Some models use electronic components or monitoring, while others are entirely mechanical and rely on hydraulic or pedal-actuated braking.
- Where should these devices be mounted? Mounting options vary by model—some under seats or in the trunk, others hitch-mounted or near the brake pedal area of the towed vehicle.
- Are there safety considerations I should know? Yes. Verify compatibility with your vehicle’s braking system, follow installation instructions precisely, and test the setup in a safe area before towing.
- Can I tow any vehicle with these systems? Most systems support a wide range, but always check manufacturer compatibility notes for your specific tow vehicle and trailer configuration.