Smlight SLZB-MR5U vs Sonoff Dongle Lite MG21 comparison

Updated June 2026

Data from Amazon and official Smlight and Sonoff sites.

2026 verdict

Smlight SLZB-MR5U wins the 2026 matchup against Sonoff Dongle Lite MG21, mainly on power, connectivity, and antenna gain. Its clearest strengths are power, connectivity, and antenna gain, and it still looks stronger on dual network and bluetooth proxy. Sonoff Dongle Lite MG21 still makes sense if its specific feature mix is your priority, but most buyers should still lean toward Smlight SLZB-MR5U. For most setups, Smlight SLZB-MR5U is the smarter buy.

Winner

Smlight

Smlight SLZB-MR5U

Price unavailable right now

Buy on Official Store

Sonoff

Sonoff Dongle Lite MG21

$19.90

Buy on Amazon USA

Feature	Smlight SLZB-MR5U	Sonoff Dongle Lite MG21	Winner
Power	USB, PoE	USB	Smlight SLZB-MR5U
Connectivity	USB, Ethernet, 2.4 GHz WiFi	USB	Smlight SLZB-MR5U
Antenna Gain	+5dBi	+3dBi	Smlight SLZB-MR5U
Dual Network	YES	NO	Smlight SLZB-MR5U
Bluetooth Proxy	YES	NO	Smlight SLZB-MR5U
Zigbee Chip Model	EFR32MG24	EFR32MG21	Different strengths
Amplifier Gain	+20dB	+20 dBm	Different strengths
Warranty	1 year	1 year	Tie
Zigbee Router	YES	YES	Tie
Z-Wave Controller	NO	NO	Tie
Thread Border Router	YES	YES	Tie
Matter Bridge	NO	NO	Tie

Winner

Smlight

Smlight SLZB-MR5U

Price unavailable right now

Buy on Official Store

+ Power: USB, PoE
+ Connectivity: USB, Ethernet, 2.4 GHz WiFi
+ Antenna Gain: +5dBi

Sonoff

Sonoff Dongle Lite MG21

$19.90

Buy on Amazon USA

- Power: USB vs USB, PoE
- Connectivity: USB vs USB, Ethernet, 2.4 GHz WiFi

Frequently Asked Questions

Which is better overall: Smlight SLZB-MR5U or Sonoff Dongle Lite MG21?

Smlight SLZB-MR5U has the stronger overall profile in this comparison, especially for power, connectivity, and antenna gain.

What is the biggest difference between Smlight SLZB-MR5U and Sonoff Dongle Lite MG21?

Power is one of the clearest differences: Smlight SLZB-MR5U lists USB, PoE, while Sonoff Dongle Lite MG21 lists USB.

Who should buy Smlight SLZB-MR5U?

Choose Smlight SLZB-MR5U if your priority is power and connectivity 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 power.

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