Edgar H.
Owner since 2016
★★★★★
Skeptical until it worked
Battery was completely flat after a cold snap — this started the engine on the first try. Compact enough for the door pocket. Video on the listing made the clamp sequence obvious.
Deal alert
A jump pack that fits in the glove box
The AstroAI B8 weighs about 329g — lighter than a hardback book — yet owners report cold-starting 2.0L diesels without flagging down another car.
Last seen around £44.99 on Amazon UK* — confirm the live price before you buy.
12V cars & bikes · 7.0L petrol · 5.5L diesel · USB power bank
Jump starterGlove-box peace of mind
AstroAI B8 Jump Starter
329g pocket pack — starts 7.0L petrol / 5.5L diesel, doubles as a USB power bank with LED torch.
4.6 (1,550+ ratings)B0FB2L7CCXRecently checked
Recently listed on Look.Product · Amazon's Choice
Last price on Amazon UK
£44.99*
* Price checked recently. Amazon prices and deals can shift hour to hour — see today's price on Amazon.
Worth a look
Amazon's Choice in jump starters for a reason — compact enough for the door pocket, strong enough for a flat January morning. Clamps flash red/green so you know if polarity is wrong.
- 329g — fits glove box or motorbike tail pack
- Rated for 7.0L petrol and 5.5L diesel engines
- Reverse-polarity protection with red/green clamp indicators
- 18W USB output for phones and tablets
- LED torch with steady and flash modes
- Drawstring pouch keeps clamps and USB lead together
What it does
Boost a flat 12V battery, charge phones from the USB ports, and light the engine bay with the built-in LED.
Cold-start boost
Owners report instant crank on a fully flat battery after a fortnight of frost. Not a replacement for a dying alternator — but enough to get home or to a garage.
Clamp reach
Leads are short by design. VW Crafter owners note the under-seat battery vs engine-bay jump posts — you may need a separate earth point if the cables will not span both.
USB power bank
Charges like a phone power bank over USB-C. Handy on motorway delays; keep 30% in reserve if you also want jump capacity the same week.
LED torch
Bright enough to find the positive terminal at 6 a.m. in January. Flash mode is visible from the roadside if you are waiting for recovery.
What to watch
Recharge every few months if the car sits idle — lithium packs self-discharge. AstroAI quotes a two-year warranty; register it when the unit arrives.
Owner feedback
What people say after a few weeks
Recent write-ups on this exact kit (F7NP · 128GB). We kept the awkward bits — app pairing trips people up more than the video quality.
4.6
★★★★★1,550+ ratings
- 572%
- 415%
- 36%
- 23%
- 14%
Feedback refreshed recently
Tiny but starts dieselsClear clamp instructionsShort leads on some vansUSB top-up between jumps
Verified owner
Daniel S.
Owner since 2010
★★★★★
Six miles from the nearest garage
Car would not turn over after Christmas idle. Charged the pack, connected clamps, engine fired immediately. No more begging for jump leads down a country lane.
Philip H.
Owner since 2014
★★★★★
2.0 diesel, no problem
Small, plenty of kick — started my 2.0L diesel without fuss. Extra USB ports and torch are handy bonuses in the same box.
Charlotte W.
Owner since 2009
★★★★★
Works — check cable reach
Started my van straight away. VW Crafter has jump posts in the bay but the battery is under the seat — supplied leads did not reach both, so I earthed on chassis metal instead.
Julia S.
Owner since 2019
★★★★★
Replaced my huge RAC pack
Old booster was enormous — this fits the glove box and still cranked a cold car in seconds. Clamp LEDs caught my reverse-polarity mistake before I turned the key.
Kent R.
Owner since 2011
★★★★★
Peace of mind for the price
Gave it four stars in my head for size, five in practice — starts without another vehicle, which is the whole point. Instructions in the box are clear enough for a first-timer.
Blake D.
Owner since 2021
★★★★★
Good — remember to recharge
Worked twice then sat in the boot for four months — third attempt needed a USB top-up first. My fault, not the unit's, but worth setting a phone reminder.
Setup
Charge to 100% when it arrives — most units ship around half full — then stow it where you can reach it without unpacking the boot.
- Step 1
Charge fully
Plug in via USB until full — out of the box ours showed about 50%. First jump attempt on a half-charged pack is asking for trouble.
- Step 2
Clamp correctly
Red to positive, black to negative or a solid chassis earth. Wait for green lights on the clamp block before you turn the key.
- Step 3
Stow in reach
Glove box or under the passenger seat — not buried under the spare wheel. You want one hand access when the battery is dead.
In the box
- Weight
- ≈329g
- Engine rating
- 7.0L petrol · 5.5L diesel
- Voltage
- 12V boost · USB power bank
- Dimensions
- ≈16 × 8.3 × 2.8 cm
- In the box
- Unit, smart clamps, USB cable, pouch
- Warranty
- 24 months (per manufacturer)
Last seen £44.99* — price checked recently
Check price on Amazon* Amazon pricing changes often — sometimes within the hour. The link above shows the current amount.