Dakota Alert DUAL-4k Plus
For a drive with steady traffic where knowing whether someone is coming or going matters, such as a farm or business entrance.
Amazon $329.99$329.99
The Dakota Alert DUAL-4k Plus is the better driveway alarm overall, rated 3.1 to 2.4. The Dakota Alert DUAL-4k Plus leads on wireless range and features. The Mighty Mule FM231 wins on value. The Mighty Mule FM231 costs $262.01 less ($67.98 vs $329.99).
Prices were last checked November 9, 2026. Product prices and availability are accurate as of that date and are subject to change; the price and availability shown on Amazon or the retailer's site at the time of purchase apply. As an Amazon Associate we earn from qualifying purchases.
Mighty Mule FM231
A low-cost buried vehicle sensor for a short driveway where the house sits within a few hundred feet of the sensor.
Amazon $67.98$67.98
Which should you buy?
- Choose the Dakota Alert DUAL-4k Plus for wireless range (1 mile claimed wireless range vs 400 ft claimed wireless range) and features (relay or 12 V output, per-sensor alerts vs adjustable sensitivity).
- Choose the Mighty Mule FM231 for value ($67.98 per sensor ($67.98, 1 sensor) vs $329.99 per sensor ($329.99, 1 sensor)).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every vehicle-only sensors driveway alarm; a clear win is highlighted. How we rank explains each one.
| Factor weight | Dakota Alert DUAL-4k Plus | Mighty Mule FM231 |
|---|---|---|
| Overall rating | 3.1/5 | 2.4/5 |
| Wireless range 30% | 100 1 mile claimed wireless range | 0 400 ft claimed wireless range |
| Value 25% | 0 $329.99 per sensor ($329.99, 1 sensor) | 60 $67.98 per sensor ($67.98, 1 sensor) |
| Features 25% | 25 relay or 12 V output, per-sensor alerts | 10 adjustable sensitivity |
| Expandability 10% | 75 up to 16 sensors per receiver | 50 sensor limit not published (neutral score used) |
| Warranty 10% | 33 1-year warranty | 33 1-year warranty |
Specifications
| Dakota Alert DUAL-4k Plus | Mighty Mule FM231 | |
|---|---|---|
| Detection | ||
| Sensor type | Magnetic probe | Magnetic probe |
| Detection distance | - | 12 ft |
| Adjustable sensitivity | - | Yes |
| System | ||
| Wireless range | 1 mile (claimed) | 400 ft (claimed) |
| Sensors in box | 1 | 1 |
| Receivers in box | 1 | 1 |
| Sensors per receiver | Up to 16 | - |
| Price per sensor | $329.99 | $67.98 |
| Alerts | ||
| Phone alerts (Wi-Fi) | No | No |
| Receiver power | Plug-in | Plug-in |
| Relay or 12 V output | Yes | No |
| Per-sensor alerts | Yes | No |
| Power and build | ||
| Sensor power | CR123A batteries | AA batteries |
| Sensor battery life | A year or more on three CR123A batteries (included) | Two AA batteries (not included), with a low-battery light |
| Operating temperature | -30 to 120°F | - |
| Warranty | 1 year | 1 year |