Meross MS605 Thread Smart Presence Sensor

Battery placement is the reason to look at it

Meross MS605 answers the main complaint about the MS600: the cable. It keeps the same broad idea of presence sensing, with radar, PIR motion, and ambient light in one small sensor, but moves to a CR123A battery and Matter over Thread.

That makes placement easier. A bathroom, study, hallway corner, or covered outdoor-adjacent spot can make more sense when the sensor does not have to sit near USB power. The tradeoff is range. Meross lists motion detection up to 6 m and presence detection up to 4 m, while the wired MS600 is the better fit when the sensor has to watch a larger room.

Matter is direct, but setup still starts with Meross

For third-party smart home apps, MS605 needs a hub that supports both Matter and Thread. That means a Thread-capable Apple Home, Google Home, Alexa, SmartThings, Home Assistant, or similar Matter setup has to be in place before the sensor is useful.

Meross still matters at setup. The official page says the device pairs through the Meross app over Bluetooth, then connects through a compatible Thread border router for local Matter control. A Meross hub is not required for that direct Matter path, but Meross says automations inside the Meross app require a Meross Hub expected in 2026 Q3. That distinction is important: Matter users can skip the Meross hub, but Meross-app users cannot treat the sensor as fully independent.

What to verify before mounting

Presence sensors are placement-sensitive, and a battery sensor does not remove that work. Test the sensor where people actually sit, stand, or pass through. Check whether fans, curtains, pets, robot vacuums, or HVAC movement cause false presence before using adhesive or a high ceiling mount.

The light sensor also needs an ecosystem check. Meross says Alexa currently does not support the light sensor, and Matter platforms can expose sensor details differently. If the automation depends on brightness, buy one first and confirm the exact trigger before ordering a multi-pack.

Should you buy it?

Buy MS605 if you already have Thread coverage and the room needs presence sensing where a cable would look bad or fail to reach. It is a practical alternative to Aqara FP300 when Meross' app flow, pricing, or multi-zone claims fit your setup.

Skip it if you are still missing a Thread border router, if the room is large enough to favor the wired MS600, or if your planned routine depends on a light sensor that your ecosystem does not expose. Battery presence sensing is useful, but it is not a shortcut around range, placement, or platform testing.