Liters Not Amps product guide
Clore Automotive Jump-N-Carry JNC305 12V Lithium Jump Starter
Passenger cars, powersports and marine starting up to 6L gas
Clore gives the JNC305 1000A and 300 start assist amps from a 14.8 volt, 37 watt-hour lithium pack, with 21-inch number 8 AWG leads, MaxAccess clamps and an override for a battery at zero volts. Its charging window is narrow: the manual allows 32 to 108 degrees Fahrenheit and the unit refuses to charge outside it.
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Published specifications
- Clore: 1000A / 300 start assist amps; up to 6L gasoline and 3L diesel
- Manual: lithium ion pack rated 14.8 V / 37 Wh for jump starting output
- Manual: operating 0F to 108F; charging 32F to 108F; recharge input 5V 2A
- Clore: 21-inch cable reach, number 8 AWG leads, MaxAccess clamps
- Manual: approvals listed as ETL, conforming to UL2743; USB out 5V 2.4A
- Clore: one year limited warranty plus a one-time repair service coupon
Fit and limits
Strengths
- Override is rated to engage a battery at 0.0 volts, per Clore and the manual
- Manual publishes capacity, all three temperature bands and full warranty text
- Charge state reads out on four LEDs, with a rapid blink when the pack is very low
Caveats
- Manual says the internal battery cannot be replaced once it is finished
- Unit refuses to charge outside 32F to 108F and flashes every status LED
- USB port count differs between Clore's table, the manual and the listing
Two starting numbers, and Clore publishes both
Clore's page opens with the phrase 1000A / 300 Start Assist Amps, and its feature list carries both figures as separate lines. The specification table holds only one of them: 12 Volt Start Assist Amps, 300. The listing's fields use the other, giving amperage and peak output current as 1000 A, and the title leads with 1000A.
The engine rating is where the two agree and where a buyer can actually make a decision. Clore says the JNC305 will start most passenger vehicles with engines up to six cylinders, which it puts at 6 litre gasoline and 3 litre diesel, and the listing repeats those same limits in its title and its first bullet.
The operator's manual does not print either amp figure. Its specification table describes the pack instead, giving jump starting output as 14.8 volts at 37 watt-hours. The two Clore numbers are separate lines rather than two names for one thing, and only the 300 figure appears in the specification table.
What ships, and where the descriptions drift
The listing's included-components field names the JNC305, a set of MaxAccess precision clamps, a USB wall charger, a USB-C charging cable and a microfiber carrying pouch. Clore's page agrees on the wall charger with USB-C cord and describes a microfiber bag for transport and storage, and its feature list adds MaxAccess clamps, a 21-inch cable reach and number 8 AWG output leads.
The manual's storage section does not match that. It says to disconnect the output leads and return all components to the zipper case for protection. Nothing in either box list mentions a zipper case, both name a microfiber pouch or bag, and no document we read reconciles the two.
USB ports are counted differently too. Clore's specification table lists a USB outlet line reading 1 at 2.4 amps and 1 at 1.0 amp, while the manual's specification table gives a single USB output of 5 volts at 2.4 amps and its control panel diagram labels one USB-A OUT port. The listing's bullet says USB outlet, singular. Count the ports on the unit before planning to charge two devices.
The manual's specification table, and what it leaves out
The numbers to plan around come from the manual: lithium ion battery, capacity 14.8 volts at 37 watt-hours, operating temperature 0 to 108 degrees Fahrenheit, charging temperature 32 to 108 degrees, recharge input 5 volts at 2 amps, USB output 5 volts at 2.4 amps, jump starting output 14.8 volts at 37 watt-hours, and approvals listed as ETL, conforming to UL2743.
The listing's battery capacity field reads 2500 with no unit attached, and no Clore document we read prints that number or explains it. Clore's page gives no capacity figure at all. The 37 watt-hour figure in the manual is the only capacity stated by a maker document here, so treat the listing's 2500 as unexplained rather than as a second measurement.
Protection lists also differ between the two Clore sources. The page's body names reverse polarity, backfeed, over-voltage, overheat, over-crank and short circuit protections, while its own specification table lists only reverse polarity, backfeed, over-voltage and overheat. The manual summarises them as built-in without enumerating. The page's body also writes UL274 in one sentence where its table says UL2743.
Temperature is the real constraint on this one
Three temperature bands sit in the manual and they do not overlap the way you might assume. Operating range is 0 to 108 degrees Fahrenheit. Charging range is narrower, 32 to 108 degrees, and the manual notes that range is printed on the rear of the unit. Separately it says not to store the unit below 50 degrees when you are using it as a jump starter.
The unit enforces the charging band itself. If it is outside 32 to 108 degrees when you connect the charger, all the Charge Status LEDs flash simultaneously to signal that charging has not started, and the manual's instruction is to bring the unit back inside the range before trying again. A cold garage in winter can therefore stop a charge before it begins.
For cold starts, the manual says the unit may not succeed on the first attempt in very cold conditions and suggests a second or third try, since the attempt warms the internal battery. It also says not to attempt a jump start after four attempts, and gives no reason for that limit.
Reading the lights, and charging rules
State of charge is shown on four LEDs after a press of the Status/Power button: one LED is 25 percent, two is 50, three is 75, four is at or near 100. The manual says to charge soon below 75 percent, immediately below 50, and to be at or near 100 percent before starting a vehicle. A very low pack makes the first LED blink rapidly on power-up.
Charging runs through the port marked USB-C IN with the supplied cord and adapter, and the manual says this brings the unit to full charge automatically without overcharging. It asks for a minimum six-hour charge when the unit is new, a recharge every three months when idle, stated elsewhere as every 90 days, and charging in a well ventilated area.
Two charger rules are absolute in the text. Never use a charger other than the one included, because an incompatible charger could damage the internal battery, and a regular 10-amp battery charger is specifically ruled out. USB output has its own protection: if the unit detects a short circuit in a connected device, it shuts the USB output down and flashes the first two Charge Status LEDs rapidly. The manual also documents fault indications during starting, and those belong in the manual.
Override, a sealed battery, and how service works
The override is what lets the JNC305 engage a battery at 0.0 volts, and both Clore's page and the listing lead with it. The manual states in plain words that activating the override removes all safety from the unit, and tells you to check every connection and confirm that a very low or totally dead battery is the only problem first. The button timing and the rest of the procedure are in the manual, which is where they should be read.
The battery is not a serviceable part. Asked directly whether it can be replaced, the manual answers no, because the battery connections inside the unit make it impossible. Disposal instructions say the lithium-based battery must be recycled or disposed of properly, and the service section says only identical original-equipment replacement parts should be used in any repair.
Warranty is one year from the date of original end user purchase, extending to each person who acquires lawful ownership within that year, and void if the product has been abused, altered, misused, or improperly packaged and damaged in return shipping. Failures inside 30 days go back to the place of purchase; from day 31 to day 365 the product is sent to Clore for service, with a valid dated sales receipt required and full details at Clore's repairs page. Clore's product page adds an included repair service coupon for a one-time fixed-fee repair after the warranty year.
Check the current listing
Confirm the model, included parts and availability before ordering.
Primary sources
- Clore Automotive product page and specification table for the JNC305
- Clore Automotive JNC305 operator's manual
Primary sources checked .
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