Dakota Alert Smart DUAL Probe 4000
The most capable kit here, for a gated property or business that wants direction-aware phone alerts and outputs to drive other equipment.
Amazon $369.99$369.99
Magnetic probe1 mile1
2.4/5
A low-cost buried vehicle sensor for a short driveway where the house sits within a few hundred feet of the sensor.
- Magnetic probeSensor
- 400 ft (claimed)Wireless range
- 1Sensors in box
- Chime receiverAlerts
Check price at Amazon$67.98
Price checked November 9, 2026. As an Amazon Associate we earn from qualifying purchases.
Pros
- Lowest-priced vehicle-only kit here
- Buried sensor ignores people and animals
- Sensitivity knob to tune out traffic on a nearby road
Cons
- Claimed 400 ft range is the shortest here, so the house needs to be close to the drive
- Sensor has to be buried
- No relay output or phone alerts
How it scores
The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its sensor type. How we rank explains each one.
Specifications
| Model number | FM231 |
|---|---|
| Detection | |
| Sensor type | Magnetic probe |
| Detection distance | 12 ft |
| Adjustable sensitivity | Yes |
| System | |
| Wireless range | 400 ft (claimed) |
| Sensors in box | 1 |
| Receivers in box | 1 |
| Price per sensor | $67.98 |
| Alerts | |
| Phone alerts (Wi-Fi) | No |
| Receiver power | Plug-in |
| Relay or 12 V output | No |
| Per-sensor alerts | No |
| Power and build | |
| Sensor power | AA batteries |
| Sensor battery life | Two AA batteries (not included), with a low-battery light |
| Warranty | 1 year |
Alternatives in this sensor type
Dakota Alert DCPA-4k Plus Probe
The classic buried-probe kit for a long rural drive where you want to hear about cars and trucks and ignore wildlife.
Amazon $259.99$259.99
Magnetic probe1 mile1
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
Magnetic probe1 mile1
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