btfarm SL21 Solar String Lights, 2 Pack, 150 LEDs

1 / 7

Product guide

btfarm SL21 Solar String Lights, 2 Pack, 150 LEDs

btfarm SL21 solar string lights are a two-pack of warm-white outdoor decorative lighting with 150 LEDs per listing description and eight operating modes. Solar power avoids a mains lead at the lights, while the stated 15+2 m length is useful for decorating a garden, balcony or party area.

At a glance

Eight selectable modes, with a stated memory function that retains the last mode after switching off.
The manufacturer describes the string as 15 metres of lights plus 2 metres of cable, with 150 LEDs.
Solar panel is intended to charge outdoors, including when the lights are used inside.

Price

£13.59Save 15%

Reference price: ~~£15.99~~

Price checked: 13 Nov 2026

View offer Ahead of Black FridayExplore the selection

Pros and cons

Pros

A pair of solar-powered strings can be arranged in separate decorative areas without running mains power to each string.
Eight lighting modes offer alternatives to a steady appearance for seasonal and event decoration.
Flexible copper wire can be shaped around objects or along garden features, according to the listing.

Technical specifications

20 specifications

Identity
Brand	btfarm
Model	SL21

Lighting
Light source	LED
Light colour	Warm White
Colour temperature	2700 Kelvin
Number of lights	150

Power and battery
Power configuration	Solar Powered
Battery capacity	800mAh
Solar collector	monocrystalline silicon, 2V 280mA

Connectivity and controls
Wireless connection listed	USB
Control methods listed	Touch
Mode control	There are two buttons on the back of the solar panel, one is on or off, the other is the operation mode

Dimensions and installation
Stated string and cable length	15+2 M (15M of light string + 2M of cable)
Distance between LEDs	10CM
Form factor	String
Weight listed	0.26 Kilograms

Materials and protection
Material listed	Copper, Plastic
Water resistance listed	Waterproof

Pack details
Number of packs	2
Battery listing	1 Lithium Polymer batteries required. (included)

What to know before buying

Listing details to confirm

The title gives 15M/50FT and 150 LEDs, while the specification states 15+2 m including cable and other listing details give 17 Metres. Battery details are inconsistent: the listing says a Lithium Polymer battery is included, while the specification gives an 800mAh capacity without identifying chemistry. USB and Touch are listed as connectivity and control fields despite the solar-panel description specifying physical buttons. Confirm the selected listing's precise length, battery and control details before buying. Charge the solar panel outdoors even if using the lights indoors.

What’s in the box

Included

User manual
2 solar string lights
Mounting screws

Who is it for?

A good fit for

Garden, balcony and patio decoration where solar-powered string lighting is preferred.
Buyers who want several lighting modes and a warm-white decorative glow for gatherings or seasonal displays.

Less suited to

Buyers who need a guaranteed runtime, charging time or dependable performance through low-sunlight conditions, none of which is specified here.
Buyers who need a confirmed exact overall length or battery configuration without checking the conflicting listing details.

btfarm SL21 Solar String Lights, 2 Pack, 150 LEDs · photo 2 — Additional product photo 2

Customer reviews on Amazon

4.3 / 5 · 3,725 ratings

5 stars67%67%
4 stars17%17%
3 stars7%7%
2 stars3%3%
1 star6%6%

Customer feedback describes a gentle glow, easy installation and lights that can stay on into the early hours. Some customers also report good charging and weather durability, while others mention sections not working or batteries no longer holding charge. That makes the reported longevity and reliability relevant for decorative use, but customer experiences do not establish a runtime or guarantee how the solar system will perform in a particular garden.

Positive themes

Customers report a gentle glow and easy installation.
Some customers say the lights remain on into the early hours and charge well during the day.

Negative themes

Some customers report that half the lights did not work.
Some customers report batteries stopping holding charge.

Mixed feedback

Feedback differs on charging and durability, with reports of good weather performance alongside concerns about reliability and battery life.

Frequently asked questions

How long are the lights?

The specification says 15+2 m, defined as 15 m of light string and 2 m of cable. The title also states 15M/50FT, and a separate details field says 17 Metres, so confirm the length shown for the selected listing.

How many lighting modes are offered?

The listing claims eight modes and says a memory function saves the last mode. It describes two buttons on the solar panel for power and mode selection.

Can these be used indoors?

The listing describes indoor use, provided the solar panel is placed outside to charge.

What is included?

The manufacturer's contents list specifies a user manual, two solar string lights and four screws. A separate battery field says one Lithium Polymer battery is included, but battery details are inconsistent elsewhere in the listing.