Sonoff · Dongle-LMG21

Sonoff Dongle Lite MG21 compact Zigbee/Thread USB coordinator

Name: Sonoff Dongle Lite MG21 compact Zigbee/Thread USB coordinator
Brand: Sonoff
SKU: SONOFF-DONGLE-LMG21
Price: 699 MDL
Availability: InStock

699 MDLIn stock

USB coordinators

Zigbee

Thread

Manufacturer images

699 MDLIn stock

Buy with installation

Check compatibility

Connectivity: Zigbee, Thread
Radio chip: Silicon Labs EFR32MG21
Antenna: External, fixed (folding)

The 43 mm body with its tilting antenna takes just one server USB port, and the bundled 0.5 m extension keeps the radio clear of USB 3.0 noise. Zigbee 3.0 out of the box, Thread after a reflash.

25 specifications from manufacturer documents

We deliver across Moldova. Availability, delivery timing and cost are confirmed with a manager before order fulfilment.

The right choice starts with specifications

Device passport

SKU: SONOFF-DONGLE-LMG21 · Document model: Dongle-LMG21

Specifications checked against the linked manufacturer documents.Checked 18 October 2026

Connectivity and compatibility8

Connectivity — what it means The wireless link or network the device uses. Wi-Fi connects straight to the router; Zigbee, Thread and Bluetooth Mesh work through a hub or gateway.	Zigbee, ThreadOut of the box: Zigbee 3.0 (IEEE 802.15.4). Thread only after flashing OpenThread RCP or MultiPAN RCP firmware with the official SONOFF Dongle Flasher; the stick then works with an OpenThread border router (Matter over Thread) [1]
Compatible software — what it means Which smart-home software the coordinator works with according to the maker's documentation: ZHA and Zigbee2MQTT for Zigbee, OpenThread Border Router for Thread, Z-Wave JS for Z-Wave. The coordinator only works together with such software on a server or mini PC.	Home Assistant ZHA, Zigbee2MQTT, openHAB, ioBroker, OpenThread Border RouterHome Assistant via ZHA (official guide); OpenThread Border Router after flashing OpenThread RCP. The maker also states eWeLink CUBE support. Domoticz and Jeedom are not listed for this model in the maker's table [3]
Transmit power — what it means The coordinator's maximum radio output. Higher power gives a steadier link to distant devices, but range in a home depends more on walls and the number of routers in the network.	20 dBmThe spec sheet reads 'Max 20 dBi + antenna gain 2 dBi': 20 is the chip output (meant as dBm), the antenna adds 2 dBi. The EU declaration in the Quick Guide states Zigbee ≤ 10 dBm [2]
Antenna — what it means An external detachable antenna can be turned or replaced with another; an internal one sits inside the housing. The antenna gain (dBi) is in the note.	External, fixed (folding)Fixed folding antenna on a hidden hinge, rotates within 180°; 2 dBi gain; antenna made of TPEE [5]
Wireless range — what it means The stated radio range, usually in open space. Walls and floors cut it noticeably.	135 mOpen space, line of sight [2]
Network devices (per maker) — what it means How many devices the maker says a network with this coordinator can handle. The real limit depends on firmware and the number of routers in the network; direct connections to the stick itself are usually fewer.	Not stated by the manufacturer
Radio frequencies and transmit power	2.4 GHz (EU: 2405–2480 MHz) [6]
Supported operating systems	Windows, Ubuntu, Raspberry Pi OS, Docker; macOS with a driver installed [2]

Model and version4

Radio chip — what it means The chip that handles the radio link. It determines which firmware is available, support in Zigbee2MQTT, ZHA and Z-Wave JS, and the memory headroom for large networks. Silicon Labs (EFR32) and Texas Instruments (CC) chips use different firmware and drivers.	Silicon Labs EFR32MG21 [2]
Radio chip memory (Flash / RAM) — what it means The chip's flash and RAM size. More memory leaves room for the routing tables of large networks and for future firmware, including Thread and Matter.	Not stated by the manufacturer
USB-to-serial chip — what it means The chip through which the radio talks to the computer over USB. CP210x and CH9102 drivers are already in Linux and Home Assistant OS; on Windows they sometimes need installing manually. On some sticks USB is built into the radio chip itself.	Silicon Labs CP2102 / CP2102NCP2102(N). Linux and Raspberry Pi OS already include the driver; on Windows and macOS the maker's guide says to install it manually [2]
Colour — what it means The housing colour of this model. Other colours in the same series are separate products.	Grey'Dim gray' per the maker [7]

Control and features3

Operating modes (firmware) — what it means Which role the radio can take with the maker's official firmware: a Zigbee coordinator creates and runs the network, a Zigbee router only extends an existing one, a Thread radio (RCP) works with an OpenThread border router, and MultiPAN runs Zigbee and Thread on one chip at once.	Zigbee coordinator, Zigbee router (repeater), Thread radio (OpenThread RCP), Zigbee and Thread at once (MultiPAN)Factory firmware: Zigbee coordinator (Zigbee NCP). Zigbee router, OpenThread RCP and MultiPAN RCP (Zigbee and Thread at once) are installed with the SONOFF Dongle Flasher [4]
Factory firmware — what it means The firmware the stick ships with: the stack and, where stated, its version (e.g. EmberZNet or Z-Stack). It decides which driver to pick in Zigbee2MQTT or ZHA on first connection.	Zigbee NCP (EmberZNet stack), coordinator; version not stated [5]
Firmware update method — what it means How firmware is changed or updated. Over USB it takes a few minutes from a browser or a Home Assistant add-on; older sticks need a separate hardware programmer.	Over USB, no programmerWith the SONOFF Dongle Flasher web tool in a browser or the SONOFF Dongle Flasher Home Assistant add-on; no programmer needed [4]

Housing and installation5

USB connector — what it means Whether the stick plugs straight into a USB-A port or connects by cable to a USB-C socket on its housing. The radio is best kept away from USB 3.0 ports and the computer case; an extension cable is used for that.	USB-A plugThe stick plugs straight into a USB-A port or via the included extension cable (official photos and Quick Guide drawing) [6]
Housing material — what it means The plastic or metal the housing and cover are made of. Polycarbonate (PC) usually withstands impact and heat better than ABS; a clear cover lets you see the module’s indicators without opening the box.	PlasticSONOFF 2026 catalogue: PC+ABS housing, TPEE antenna. The product page says 'Aluminum, PC+ABS', so the maker's data disagree [7]
Dimensions — what it means The device’s size in millimetres as the maker states it. Check that it fits the wall box, niche or shelf.	18.6 × 10.1 × 133 mmWith the antenna raised. Per the official dimension drawing the body is 43 mm long and the antenna 90 mm [2]
Weight — what it means The device’s weight without packaging, per the maker.	8.8 g [7]
Certifications — what it means Standards and certifications the maker lists for this model (for example CE, RoHS, Zigbee 3.0, Matter).	CE, FCC, RoHS [7]

Operating conditions2

Operating temperature — what it means The air temperature range the device is rated for. The lower limit matters outdoors, on balconies and in unheated rooms.	−10…40 °CThe product page and its spec card state −10…60 °C [2]
Operating humidity — what it means The rated relative humidity range, non-condensing.	5–95% [2]

Package contents2

Package contents — what it means What comes in the box, per the maker.	Dongle Lite MG21, 0.5 m USB extension cable, quick guide [1]
Manufacturer warranty — what it means The warranty period the maker states. Confirm warranty terms in Moldova with the seller.	24 months“2-Year Hassle-Free Warranty” on the official SONOFF store page; warranty terms of a regional seller may differ [5]

Power3

Power source — what it means Where the device gets its power: 230 V mains, an adapter, USB, batteries or a built-in battery.	From the AC's USB socketFrom the host's USB port [2]
Supply voltage — what it means The supply voltage (and current, if stated) as the maker gives it. It must match your mains or adapter.	5 V ⎓ 500 mA [2]
Standby power — what it means How much power the device draws on its own while idle. It matters for devices that run around the clock.	0.06 W60 mW per the spec sheet [2]

Differences between manufacturer documents

The table shows the primary document’s value. Below is what other manufacturer documents state; we check the supplied version’s label before sale.

Wireless range: The product page says 'up to 140 m stable coverage in open spaces'

Manufacturer documents

Clear purchase details

Delivery and stock

We deliver across Moldova. Availability, delivery timing and cost are confirmed with a manager before order fulfilment.

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Warranty and documents

The warranty is at least 12 months. The exact period and conditions for equipment and installation work are stated in the sales documents and the accepted proposal. Further support is agreed for each project.

Can I return the product?

Current conditions are published on the Return policy page. Email office@casasmart.md with your order number for the steps relevant to your situation. Statutory consumer rights continue to apply.

Delivery, payment and returns

In your home

A reliable connection underpins your smart home.

A fast broadband plan does not fix weak signal through a wall. Several apps do not become one system by themselves. Placement and verified connections matter.

See the complete solution

A home office with a laptop and a network cabinet in the wall — An example routineConnectivity planned for every room.

What to check before buying

We clarify the floor area and number of levels, where the provider’s router sits, which rooms matter for work and video, and whether cable can be run. Real speed also depends on your internet plan and the device itself.
Power — From the AC's USB socket: plan it for the mounting spot.

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