Smlight SLZB Ultima vs Sonoff Dongle Lite MG21

Updated March 2026

Data from Amazon and official Smlight and Sonoff sites.

2026 verdict

For most buyers in 2026, Smlight SLZB Ultima is the safer pick. It separates itself most clearly on connectivity, z-wave controller, and dual network, while still looking better on bluetooth proxy. Sonoff Dongle Lite MG21 remains a niche alternative if its specific feature mix matters more than the rest of the comparison. That makes Smlight SLZB Ultima the clearer recommendation in 2026.

Winner

Smlight

Smlight SLZB Ultima

Price unavailable right now

BUY NOW

Sonoff

Sonoff Dongle Lite MG21

$19.90

BUY NOW

Feature	Smlight SLZB Ultima	Sonoff Dongle Lite MG21	Winner
Connectivity	USB, Ethernet, 2.4 GHz Wifi	USB	Smlight SLZB Ultima
Z-Wave Controller	YES	NO	Smlight SLZB Ultima
Dual Network	YES	NO	Smlight SLZB Ultima
Bluetooth Proxy	YES	NO	Smlight SLZB Ultima
Zigbee Chip Model	EFR32MGXX / CC26XXPX	EFR32MG21	Different strengths
Warranty	1 year	1 year	Tie
Power	PoE	USB	Tie
Zigbee Router	YES	YES	Tie
Thread Border Router	YES	YES	Tie
Matter Bridge	NO	NO	Tie

Winner

Smlight

Smlight SLZB Ultima

Price unavailable right now

BUY NOW

+ Connectivity: USB, Ethernet, 2.4 GHz Wifi
+ Z-Wave Controller: YES
+ Dual Network: YES

Sonoff

Sonoff Dongle Lite MG21

$19.90

BUY NOW

- Connectivity: USB vs USB, Ethernet, 2.4 GHz Wifi
- Z-Wave Controller: NO vs YES

Frequently Asked Questions (FAQ)

Which is better overall: Smlight SLZB Ultima or Sonoff Dongle Lite MG21?: Smlight SLZB Ultima has the stronger overall profile in this comparison, especially for connectivity, z-wave controller, and dual network.
What is the biggest difference between Smlight SLZB Ultima and Sonoff Dongle Lite MG21?: Connectivity is one of the clearest differences: Smlight SLZB Ultima lists USB, Ethernet, 2.4 GHz Wifi, while Sonoff Dongle Lite MG21 lists USB.
Who should buy Smlight SLZB Ultima?: Choose Smlight SLZB Ultima if your priority is connectivity and z-wave controller and that matters more than the competing advantages.
Who should buy Sonoff Dongle Lite MG21?: Choose Sonoff Dongle Lite MG21 if your priority is its specific strengths and that matters more than connectivity.

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