Smlight SLZB-MR3 vs Sonoff Dongle Lite MG21

Updated March 2026

Data from Amazon and official Smlight and Sonoff sites.

2026 verdict

Across the full comparison in 2026, Smlight SLZB-MR3 earns the nod. The main reason it wins is power, connectivity, and antenna gain, and dual network and bluetooth proxy strengthens that case. Sonoff Dongle Lite MG21 can still be the right pick, but only if price outweighs the wider strengths of Smlight SLZB-MR3. That is why Smlight SLZB-MR3 wins the verdict here.

Winner

Smlight

Smlight SLZB-MR3

$105.99

BUY NOW

Sonoff

Sonoff Dongle Lite MG21

$19.90

BUY NOW

Feature	Smlight SLZB-MR3	Sonoff Dongle Lite MG21	Winner
Price	$105.99	$19.90	Sonoff Dongle Lite MG21
Power	USB, PoE	USB	Smlight SLZB-MR3
Connectivity	USB, Ethernet, 2.4 GHz Wifi	USB	Smlight SLZB-MR3
Antenna Gain	+5dBi	+3dBi	Smlight SLZB-MR3
Dual Network	YES	NO	Smlight SLZB-MR3
Bluetooth Proxy	YES	NO	Smlight SLZB-MR3
Zigbee Chip Model	EFR32MG24 / CC2674P10	EFR32MG21	Different strengths
Amplifier Gain	+20dB	+20 dBm	Different strengths
Rating	4.7	4.7	Tie
Warranty	1 year	1 year	Tie
Zigbee Router	YES	YES	Tie
Z-Wave Controller	NO	NO	Tie

Winner

Smlight

Smlight SLZB-MR3

$105.99

BUY NOW

+ Power: USB, PoE
+ Connectivity: USB, Ethernet, 2.4 GHz Wifi
+ Antenna Gain: +5dBi
- Price: $105.99 vs $19.90

Sonoff

Sonoff Dongle Lite MG21

$19.90

BUY NOW

+ Price: $19.90
- Power: USB vs USB, PoE
- Connectivity: USB vs USB, Ethernet, 2.4 GHz Wifi

Frequently Asked Questions (FAQ)

Which is better overall: Smlight SLZB-MR3 or Sonoff Dongle Lite MG21?: Smlight SLZB-MR3 has the stronger overall profile in this comparison, especially for power, connectivity, and antenna gain.
What is the biggest difference between Smlight SLZB-MR3 and Sonoff Dongle Lite MG21?: Price is one of the clearest differences: Smlight SLZB-MR3 lists $105.99, while Sonoff Dongle Lite MG21 lists $19.90.
Which one looks better on price?: Smlight SLZB-MR3 is listed at $105.99, while Sonoff Dongle Lite MG21 is listed at $19.90. Sonoff Dongle Lite MG21 (better spec).
Who should buy Smlight SLZB-MR3?: Choose Smlight SLZB-MR3 if your priority is power and connectivity and that matters more than price.
Who should buy Sonoff Dongle Lite MG21?: Choose Sonoff Dongle Lite MG21 if your priority is price and that matters more than power.

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