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Cube extension lead buying guide

Updated: 23 October 2026

You are at a UK desk with a laptop brick, a monitor, a lamp and a phone charger, and the wall socket takes one plug. This cube extension lead buying guide puts the checks in order before you open the [power cube comparison](/hub/sockets-and-extension-leads/power-cube). A power cube puts sockets on the faces of a small block. Some units include a flex and a BS 1363 plug. Some push straight into the wall. Extra faces do not add extra current. Peter F., the DIY & tools editor, used the amazon.co.uk listings dated 21 October 2026. This page did not lab-test the units. A qualifying purchase can earn a commission at no extra cost to you.

You are at a UK desk with a laptop brick, a monitor, a lamp and a phone charger, and the wall socket takes one plug.

Our top picks

BEVA BEVA 4-way cube with 3 USB

Best overall

BEVA BEVA 4-way cube with 3 USB
8.9/10about £13.59
View offer
JSVER JSVER 3-outlet cube, 2 m

Best value

JSVER JSVER 3-outlet cube, 2 m
8.7/10about £13.99
View offer
VoltFlow VoltFlow cube with USB-C

Alternative

VoltFlow VoltFlow cube with USB-C
7.1/10about £21.25
View offer
On this page
  1. 1.What a power cube is, and what it is not
  2. 2.Check the plug and the shared 13 A mark
  3. 3.Read the USB line narrowly
  4. 4.Surge figure or load figure
  5. 5.What to do next

What a power cube is, and what it is not

A power cube here puts sockets on the sides of a block, not in a row. That helps when two chunky supplies would cover the next hole on a strip. It is still one appliance on one wall socket. Four faces are not four circuits. A strip is a longer bar. A tower usually offers more outlets. An eight-way tower was removed as a different product. UGREEN is borderline: the shape field says Flat, 12.5 × 7.8 × 3.3 cm. Shape is on cube extension lead vs strip. Wall versus cable is on wall cube adaptor vs extension lead.

Check the plug and the shared 13 A mark

UK mains are 230 V, with a BS 1363 plug and a BS 1362 fuse. Regulation 35 of the Electrical Equipment (Safety) Regulations 2016 requires a correctly fitted UK plug, or a conversion plug plus a BS 1362 fuse, on kit for a BS 1363 socket. A Schuko-only body is a buying problem. The JSVER cabled cube prints Type G and Type B. Status prints Type B beside a 3-pin title. Confirm the pins on arrival. The fuse is shared. Electrical Safety First says to add what may run at once and not daisy-chain. A kettle is up to 13 A, about 3,000 W. BEVA and the JSVER cabled cube both print 13 A and 10 A.
BEVA BEVA 4-way cube with 3 USB

Testsieger

BEVA BEVA 4-way cube with 3 USB
8.9/10about £13.59
View offer

Read the USB line narrowly

USB ports do not raise the mains fuse. A shared 5 V 2.4 A line, as on BEVA and the JSVER cabled cube, is for phones. The JSVER wall cube states 12 W total. VoltFlow says C1 supplies PD 65 W only when used alone. With other USB ports active, C1 is 45 W and C2 is 15 W. Reviews mention about 62–63 W on one HP laptop, so 65 W is a claim. ROOTOMA caps USB-C at 15.5 W. UGREEN claims 20 W, falling to 15 W when several ports are used.

Surge figure or load figure

A surge rating is energy in joules. A load rating is what the fuse is marked for. BEVA prints 3,250 W in a protection cell. At the 250 V also on the listing, that is a 13 A load sum, not joules. ROOTOMA does the same kind of sum. UGREEN says 2,990 W at 13 A. Fellowes does not print joules. Scottish Fire and Rescue points surge shoppers toward a multi-way bar.

What to do next

For light desk loads, a cabled cube with a master switch is the default. A laptop-shaped USB-C claim means the VoltFlow alone-port condition. The JSVER wall cube is only for light plugs you can see. Then match the job on the best cube extension lead UK page.

Common questions

Do I need a cable or a wall cube?
Take the cable if the plugs are heavy or the load is anything you would mind overheating. A wall cube is a block adaptor under BS 1363-3:2023. A cabled cube is a plug plus outlets on a flex. London Fire Brigade prefers the fused inline type. A wall cube can still suit a phone charger and a radio that stay seated, if you unplug when the case warms up.
Will USB-C on a cube charge a laptop?
Only on the listing that says so, and only inside that condition. VoltFlow claims PD 65 W on C1 when the other USB ports are empty, then 45 W and 15 W once they are in use. ROOTOMA's USB-C line is about 15.5 W. UGREEN claims 20 W, with 15 W total if several USB ports work together. A 5 V 2.4 A shared bank is for phones. Those watts are not extra mains amps.
Can a kettle share the cube?
A kettle can use the whole 13 A budget. Electrical Safety First puts one at up to 13 A, about 3,000 W. If it is on the cube, leave the toaster, the heater and the microwave off the other faces. The rule is the same for a wall cube and a cabled cube. High kitchen loads belong in the wall socket, or on a lead whose total you have already added up.
What cable length works for a desk?
Most cabled cubes here sit between 1.4 m and a claimed 2 m. Status prints 1.4 m. BEVA and VoltFlow print 1.5 m. Fellowes prints 2 m. The JSVER title says 200 cm, and one UK review says the wire is about a metre, so measure it. A cube does not unwind like a reel. To cross a room you want a longer strip or a reel.
When should I skip a cube entirely?
Skip it for more than about four mains outlets, a labelled surge rating in joules, an outdoor socket, or a permanent extra point on the wall. If the socket is scorched or the breaker trips, call an electrician. A workplace ban on block adaptors is a site rule, even when a fused wall cube is lawful at home. No listing in this set prints an IP code.

Related pages

How to use a power cube

Power cube

Best cube extension lead UK

Cube extension lead vs strip

Wall cube adaptor vs extension lead

Sources

Sources taken from the research digest. Shelf prices, stars and review counts are the amazon.co.uk figures in the stored listings, dated 21 October 2026. This page did not run a lab test.

  1. Electrical Safety First — extension leads, cable reels and block adaptors (retrieved 22.10.2026)
  2. Electrical Safety First — overloading sockets (retrieved 22.10.2026)
  3. Electrical Safety First — ratings of electrical appliances (retrieved 22.10.2026)
  4. London Fire Brigade — cables, fuses and leads (retrieved 22.10.2026)
  5. Which? — how to avoid overloading plug sockets (retrieved 22.10.2026)
  6. Scottish Fire and Rescue Service — electrical safety (retrieved 22.10.2026)
  7. Electrical Equipment (Safety) Regulations 2016, regulation 35 (retrieved 22.10.2026)
  8. BSI — BS 1363-3:2023 adaptors (retrieved 22.10.2026)