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Head-to-head · Best Level 2 Portable EV Chargers

J+ BOOSTER 2 vs MUSTART 40A Level 2 Portable

Which is the better buy? Side-by-side on rating, price, strengths, and watch-outs — with the published ratings we averaged to get there.

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The short answer

J+ BOOSTER 2 is the only one of the two with a published score (4.6); MUSTART 40A Level 2 Portable has none, so this is not a close call so much as an unmeasured one. J+ BOOSTER 2 is best for: drivers who want one very rugged 40 A charger to use at home and carry on road trips. Read the strengths below before deciding.

J+ BOOSTER 2
Higher ratedRanked #2 in Best Level 2 Portable EV Chargers
J+ BOOSTER 2
2 sources

The J+ Booster 2 is a 40 A, dual-voltage portable J1772 charger with an aluminium body and a 21 ft or 25 ft cord. It takes swappable NEMA 14-50 and NEMA 5-15 adapters. InsideEVs drove two pickup trucks over it, froze the cord and submerged the unit, and the charger kept working; it scored 4.4/5. EVchargerReviews.net (4.7/5) ran it at 40 A for hours with no thermal throttling and called it the most premium portable unit it had tested. It suits drivers who want one rugged charger for the garage and the road. Anyone with an existing NEMA 14-50 outlet installed upside down, or on a tight budget, should look elsewhere.

Strengths
  • — Kept working after InsideEVs drove an F-150 Lightning and a Rivian R1T over it
  • — Ran for hours at 40 A with no thermal throttling in a 50 kWh stress test
  • — IP67-rated, and it passed InsideEVs' submersion test after more than 30 minutes underwater
Watch-outs
  • — Input cables are only about a foot long, so outlet position and orientation matter
  • — The most expensive portable charger EVchargerReviews.net has tested
  • — The cord earned only an average score in InsideEVs' deep-freeze test
Buy at jplusbooster.comFull review →
MUSTART 40A Level 2 Portable
Ranked #5 in Best Level 2 Portable EV Chargers
MUSTART 40A Level 2 Portable
Unrated2 sources$179as of Oct 10

The MUSTART 40A is a long-running, widely-sold portable Level 2 charger that delivers the full 9.6 kW with a generous 25-foot cable for a moderate price. The main cautions are reports of inconsistent safety certifications and the lack of smart features.

Strengths
  • — Full 40A / 9.6 kW output, about 2.5x faster than a 16A Level 2 charger
  • — IP65 control box and IP67 connector with lightning, overvoltage, overheat and overcurrent protection
  • — Lower price than the Grizzl-E Mini Connect while charging at the same 40A
Watch-outs
  • — No Wi-Fi or app, and no scheduling on the base portable model
  • — A minority of users report J-plug or charging-port issues over time
$179 · Buy at mustartpower.comFull review →

How they stack up

J+ BOOSTER 2

The Booster 2 is a premium alternative to the Grizzl-E Mini Connect (40A) and the Splitvolt 40A NEMA 14-50. Its main selling points are a crush-rated aluminium body, IP67 sealing and swappable locking plug adapters. Its controls are a single button and LED indicators, so buyers who want an LCD and app scheduling may prefer the Lectron 40A J1772 Portable (Wi-Fi).

MUSTART 40A Level 2 Portable

A value alternative to the Grizzl-E Mini Connect with the same 40A output and an equally long 25-foot cable, but no Wi-Fi or app; it costs more than the Splitvolt but offers a longer cord and adjustable current.

Specs side-by-side

SpecJ+ BOOSTER 2MUSTART 40A Level 2 Portable
Max Current40 A (adjustable from 6 A)—
Max Power9.6 kW (NEMA 14-50)—
Cable Length21 ft or 25 ft25 ft
ConnectorJ1772J1772
Input AdaptersNEMA 14-50; NEMA 5-15 optional—
WeightUnder 8 lb (21 ft version)—
Ingress RatingIP67—
Crush Rating6,600 lb—
Max Output—40A / 9.6 kW
Adjustable Amperage—16 / 20 / 24 / 32 / 40A
Plug—NEMA 14-50
Enclosure—IP65 box / IP67 connector
Connectivity—None
Warranty—2-year
← See the full ranking of best level 2 portable ev chargers