# AstroAI B8 Car Jump Starter Power Pack, 7.0L Petrol / 5.5L Diesel, 329g

Source: https://www.ranked10.co.uk/tech/best-jump-starter/astroai-b8
Ranked #2 in "Best Jump Starter 2026: 10 Car Battery Boosters Ranked": https://www.ranked10.co.uk/tech/best-jump-starter

- Price: £31.99 (checked on Amazon UK on 2026-09-03)
- Amazon rating: 4.6 from 1,976 ratings
- Buy on Amazon: https://www.amazon.co.uk/dp/B0FB2L7CCX?tag=ranked10-21

The AstroAI B8 is a 12V lithium polymer jump starter, and it takes second place in our jump starter ranking. It is the value pick: at GBP 31.99 it is the cheapest pack in the ten, and at 8.3 x 16 x 2.8 centimetres it drops into a glovebox and stays there. Everything on this page comes from its Amazon listing rather than from our own testing: the price, the specification table, the spread of its 1,976 customer ratings, and two review quotes copied word for word.

The specification is worth reading closely, because it contradicts itself on weight. The product title and the Item Highlight field both sell the B8 as "Ultra-light 329g", while the specification table on the same page gives the item weight as 650 g — very nearly double. We cannot tell you which figure is right, so both appear in the table below with the field each one came from. The other number to note is the amperage: the table declares 2,000 amps, yet the title leads on engine size instead, quoting 7.0 litres of petrol and 5.5 litres of diesel.

## Specification

| Field | Value |
|---|---|
| Brand | AstroAI |
| Model number | B8 |
| Manufacturer part number | B8 |
| Manufacturer | AstroAI |
| Amperage | 2000 Amps |
| Voltage | 12 Volts |
| Battery cell composition | Lithium Polymer |
| Battery capacity | 8000 Milliamp Hours |
| Compatible vehicle type | Automotive |
| Automotive fit type | Universal Fit |
| Item dimensions (D x W x H) | 8.3 x 16 x 2.8 centimetres |
| Item weight (specification table) | 650 g |
| Item weight (title and Item Highlight) | 329 g |
| Item highlight (as listed) | Ultra-light 329g Car Battery Booster Jump Starter, 10 Smart Safety Protections, Emergency LED Light, Portable Storage Bag |
| Included components | AstroAI B8 Car Battery Jump Starter, Pack with Giftbox, Smart Jumper Leads, Storage bag |
| Number of items | 1 |
| Manufacturer warranty | 2-year manufacturer's warranty |
| ASIN | B0FB2L7CCX |

## Questions people ask

**What size engine will the AstroAI B8 start?**

The title quotes 7.0 litres of petrol and 5.5 litres of diesel, from a declared 2,000 amps. Those are the listing figures rather than ones we measured, and how close you get depends on the engine and how flat the battery is.

**How much does the AstroAI B8 actually weigh?**

The listing publishes two different answers. The product title and the Item Highlight field both say 329g; the specification table says 650 g. We report both because we cannot tell which one AstroAI intends, and the difference is close to double.

**Can it charge a phone?**

The specification table gives the battery as 8,000mAh, and the listing sells the B8 as a power pack as well as a jump starter. The listing does not state how many phone charges that works out to.

**What comes in the box?**

The listing names the B8 jump starter itself, a giftbox pack, smart jumper leads and a storage bag. It also lists an emergency LED light on the unit.

**What safety features does the listing claim?**

AstroAI states the B8 has 10 smart safety protections and describes the leads as smart jumper leads. That is the maker claim as published on the listing; we have not tested it.

**Will it fit in a glovebox, and what warranty does it carry?**

The specification table gives 8.3 x 16 x 2.8 centimetres, which is glovebox size, and the listing states a 2-year manufacturer warranty.