SMLIGHT SLZB-Ultima Review: Every Smart Home Radio in One Four-Antenna Gateway
Zigbee, Thread, Z-Wave Series 800 and a Bluetooth proxy, plus USB passthrough, on a PoE-powered coordinator.
The SLZB-Ultima is SMLIGHT's everything box: Zigbee on both Silicon Labs and Texas Instruments silicon, Thread border routing, a Z-Wave Series 800 controller, a Bluetooth proxy and USB-over-Ethernet passthrough, with four external antennas and PoE. The idea is that one device on the network replaces every dongle hanging off your Home Assistant server, while sitting somewhere with actual radio coverage. Dual network mode means Zigbee and Thread run simultaneously. It is the most capable coordinator in the range and, being brand new, also the least proven.
- Consolidating every radio into one device
- Mixed Zigbee, Z-Wave and Thread homes
- PoE installations
- Large Home Assistant setups
Pros
- Covers Zigbee, Thread, Z-Wave and Bluetooth in one device
- Both Silicon Labs and Texas Instruments Zigbee radios
- Z-Wave Series 800 controller
- Dual network mode: Zigbee and Thread simultaneously
- USB-over-Ethernet passthrough for another dongle
- Four external antennas
- Ethernet with PoE, plus USB and Wi-Fi
Cons
- Brand new, with almost no independent user experience
- Becomes a single point of failure for every protocol
- Z-Wave is frequency region-locked
- Chip models, amplifier gain, antenna gain and dimensions are not documented
- No Matter bridging
- 2.4 GHz Wi-Fi only, and a one year warranty
Who is the SLZB-Ultima for?
It targets the setup that has accumulated hardware: a Zigbee coordinator, a Z-Wave stick, a Bluetooth adapter, maybe a spare dongle shared over the network. This gateway covers all of it, and PoE means the whole radio stack moves to a single well-placed spot instead of sitting behind a server in a cupboard. Four external antennas signal the intent: this is aimed at large networks where reception across several protocols matters at once.
What it offers
Zigbee 3.0 with coordinator and router roles across both Silicon Labs and Texas Instruments radios, so either firmware ecosystem is available natively. Thread border router capability for Matter accessories, with dual network mode so Zigbee and Thread operate at the same time. A Z-Wave Series 800 controller, the current generation. A Bluetooth proxy for relaying BLE sensors to Home Assistant. And USB-over-Ethernet passthrough, which exposes another USB device connected to the gateway as though it were plugged into your server. Connection is Ethernet with PoE, USB or 2.4 GHz Wi-Fi, and both Home Assistant and Zigbee2MQTT are supported.
What to know before you buy
It is new, and there is very little independent experience to draw on yet, which is a real consideration for a device that would become the single point of failure for every protocol in your house. Z-Wave is frequency region-locked, so the unit must match your country. Several specifications are undocumented, including the exact chip models, amplifier gain, antenna gain and physical dimensions. It does not bridge Zigbee or Z-Wave devices to Matter controllers. Wi-Fi is 2.4 GHz only, and the warranty is one year.
Is the SLZB-Ultima worth it?
As the flagship it carries a flagship price, and the calculation is consolidation: if you would otherwise buy a multi-radio Zigbee gateway plus a Z-Wave controller plus a Bluetooth solution, one device is both cheaper and better positioned. The counterweight is concentration of risk and novelty: everything depends on one new product with little track record. A staged approach, keeping a spare coordinator on hand, is sensible until it proves itself in your setup.
Frequently asked questions
Which protocols does the SLZB-Ultima handle?
Zigbee 3.0, Thread (as a border router), Z-Wave Series 800, and Bluetooth as a proxy for Home Assistant. It also passes another USB device over the network.
Can it run Zigbee and Thread at the same time?
Yes. Dual network mode is supported.
Does the Z-Wave radio work everywhere?
No. Z-Wave frequencies are region specific, so the unit must match your country to work with your existing Z-Wave devices.
What does USB passthrough do?
It makes a USB device plugged into the gateway available over the network as if it were connected to your server, which is useful for a dongle you want relocated too.
Should I make it my only coordinator?
That is its purpose, but it is a very new product with little independent experience behind it, so keeping a spare coordinator until it proves stable in your setup is a reasonable precaution.









