The GOOLOO A9 Ultra is the better jump starter overall, rated 4.0 to 3.9. The GOOLOO A9 Ultra leads on features and capacity. The WOLFBOX MegaVolt 24Air wins on warranty. The GOOLOO A9 Ultra costs $5 less ($179.99 vs $184.99).
Prices were last checked November 9, 2026. Product prices and availability are accurate as of that date and are subject to change; the price and availability shown on Amazon or the retailer's site at the time of purchase apply. As an Amazon Associate we earn from qualifying purchases.
GOOLOO’s top combined jump starter and inflator, rated for any gas engine and big diesels, with fast 100 W USB-C charging. Worth it if you want one heavy-duty tool for trucks, RVs and travel.
Amazon $179.99For truck and SUV owners who want a jump starter and a fast tire inflator in one box. It covers gas engines up to 10 liters for little more than the 16Air.
Amazon $184.99Each factor is scored 0-100 against the same fixed reference points for every heavy duty jump starter; a clear win is highlighted. How we rank explains each one.
| Factor weight | GOOLOO A9 Ultra | WOLFBOX MegaVolt 24Air |
|---|---|---|
| Overall rating | 4.0/5 | 3.9/5 |
| Value 40% | 77 $179.99 for its size | 76 $184.99 for its size |
| Features 35% | 80 manual override, rated to -4 °F, USB-C charging | 70 rated to -4 °F, USB-C charging, IP64 |
| Capacity 15% | 75 99.9 Wh battery | 61 88.8 Wh battery |
| Warranty 10% | 25 1.5-year warranty | 50 2-year warranty |
| GOOLOO A9 Ultra | WOLFBOX MegaVolt 24Air | |
|---|---|---|
| Starting | ||
| Rated engines | all gas, 12 L diesel | 10 L gas, 6 L diesel |
| Peak amps (maker) | 6,000 A | 4,000 A |
| Cranking amps | 480 A | - |
| Voltage | 12 V | 12 V |
| Manual override | Yes | - |
| Lowest operating temperature | -4 °F | -4 °F |
| Battery and charging | ||
| Chemistry | Lithium-ion | Lithium-ion |
| Capacity | 99.9 Wh | 88.8 Wh |
| Capacity (mAh) | 27,000 mAh | 24,000 mAh |
| USB-C input | 100 W | 65 W |
| Recharge time | 1.5 hours | 2 hours |
| USB outputs | USB-C 100 W, USB-A 5 V/2.4 A | USB-C 65 W, USB-A 18 W, USB-A 12 W |
| Build | ||
| Flashlight | Yes | Yes |
| Air compressor | Yes | Yes |
| Water resistance | - | IP64 |
| Dimensions | 11.4 x 6.49 x 3.18 in | 9.39 x 5.28 x 2.16 in |
| Weight | 4.8 lb | 3.4 lb |
| Warranty | 1.5 years | 2 years |
| Released | 2026-09 | 2025-06 |
