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ProMariner

ProMariner ProSport HD 20A 3-Bank Waterproof Onboard Battery Charger

  • Based on 830 reviews
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Availability: In Stock.
Fulfilled by Amazon
Arrives Monday, Oct 26
Order within 21 hours and 29 minutes
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Pattern Name: Charger


Style: 12/24/36V, 20 Amp, 3 Bank


Features

  • ProSport HD 20A Triple Bank Waterproof Marine Battery Charger (Part Number 44021) replaces the old ProMariner Gen 3 ProSport 20 plus (part number 43021)
  • ProMar Digital Technology: Microprocessor and software controlled charging technology for fast, precise charging
  • Distributed-On-Demand Technology: 100% of all available charging amps are utilized by distributing unused charging amps to any one or combination of all batteries as needed
  • Heavy Duty Tri-Surface Extruded Heat Sink Design: Upper, lower and rear facing heat sink design for optimal cooling while delivering true rated constant current charging amps during its two charge mode
  • Expanded LED Display with Completion Status Gauge: LED fuel gauge style completion status. Four color multi-stage mode LED status bar. Multi-stage Charge Mode, System Check OK, individual Battery Status and Battery Type indication

Description

The new ProSport HD features a lightweight, tri-surface heatsink design. This delivers significantly faster charging through optimal cooling, while delivering true rated constant current charging amps during charge mode. Fully automatic multi-stage charging enhances battery performance while extending battery life.

Brand: ProMariner


Color: Gray/ Yellow


Product Dimensions: 8.7"D x 16.4"W x 6.3"H


Item Weight: 7.2 pounds


Output Voltage: 36 volts_of_direct_current


Output Voltage: 36 volts_of_direct_current


Input Voltage: 120 volts


Battery Charge Time: 5 hours


Current Rating: 20 A


Amperage: 20 A


Compatible Devices: boat


Connector Type Used on Cable: Battery Clamps


Number of Ports: 3


Item Dimensions D x W x H: 8.7"D x 16.4"W x 6.3"H


Item Weight: 7.2 pounds


Specification Met: RoHS, UL, CE, FCC, CEC, RCM


Color: Gray/ Yellow


Brand: ProMariner


Mfr Part Number: 44021


UPC: 031669440210


Number of Items: 1


Manufacturer: ProMariner


Item Highlight: IP67; Distributed-On-Demand charging; LED status display; lithium, flooded, AGM and gel compatible


Unit Count: 1 Count


Built-In Media: Battery charger, AC/DC power cables


Item Type Name: boating-battery-chargers


Model Number: 44021


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Oct 26

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
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  • Financing through Google Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

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Top Amazon Reviews

    • Pro Mariner 3 Bank Triple Charger
Pattern Name: Charger Style: 12/24/36V, 20 Amp, 3 Bank
It all of a sudden stopped working one day, I called the warranty department and it was replaced with no problems. It worked great until it stopped working. Replacement works great also so far no issues. Would recommend this item.
Reviewed in the United States on April 13, 2025 by Mudgirl
    • A much needed accessory
Pattern Name: Charger Style: 12/24/36V, 20 Amp, 3 Bank
I had a similar older model, 11 years old, that quit. I spoke to customer service and was provided honest up to date information. I replaced with a new model. Was fairly easy to install and works like a charm. Keeps all 3 batteries fully charged and ready for use. Don't have to worry if battery running bilge pump is going to die. Highly recommend. ... show more
Reviewed in the United States on May 9, 2021 by Cary Scott
    • Money well spent!
Pattern Name: Charger Style: 12/24/36V, 20 Amp, 3 Bank
Review Image by Bob411
These ProSport chargers are the best. This is the third unit I’ve had on as many boats. I maintain three batteries wired for one 12-volt circuit and one 24-volt circuit. Not only are my systems always charged, keeping the batteries fully charged and not allowed to discharge to a critical level has extends their life. Just as important is the customer service. Every time I contacted them, I received a response in 24 hours and had my issue solved in a quick friendly manner. Go for it, you won’t be sorry! ... show more
Reviewed in the United States on September 21, 2024 by Bob411
    • Easy to connect and it is super quite.
Pattern Name: Charger Style: 12/24/36V, 20 Amp, 3 Bank
This is the second unit I have purchased. The first worked great but I hade a major short circuit that fried one of the 3 leads. the unit performs as listed in their promo
Reviewed in the United States on May 17, 2026 by Leo D. Peloquin
    • 3 gang battery charger
Pattern Name: Charger Style: 12/24/36V, 20 Amp, 3 Bank
The unit was quite easy to install and has performed well.
Reviewed in the United States on September 13, 2025 by Robert M. Saindon
    • Great product 👌
Pattern Name: Charger Style: 12/24/36V, 20 Amp, 3 Bank
Looks good, works great, I'm extremely satisfied with this product I definitely recommend it
Reviewed in the United States on August 31, 2025 by Rw Wilson
    • Same part number but different charger
Pattern Name: Charger Style: 12/24/36V, 20 Amp, 3 Bank
I bought this item because it was suppose to charge life pod also I bought it a couple of years ago but didn’t have life pod batteries then but it was for a further use Now I have life pod only to find out the unit they sent s the exact same part number but it doesn’t charge life pod these are great chargers but I feel like I got ripped off and they sent me one of the ones that wasn’t equipped for lithium. It’s looks the same and what I bought wasn’t the same I thought the lithium light didn’t light up til you actually hooked it up to a life pod battery ... show more
Reviewed in the United States on March 15, 2025 by Amazon Customer
    • Customer service was excellent!
Pattern Name: Charger Style: 12/24/36V, 20 Amp, 3 Bank
Review Image by Tom T
I bought this unit in May of 2022. This unit was used to maintain two batteries to a trolling motor and one battery for the boat gas motor. After a year and a half of use, one of the 3 banks stopped maintaining/working. I went on Promariners website and followed directions for a warranty claim. It is warranted for three years. I forwarded them a copy of my Amazon receipt along with a picture of the serial number. Within about 24 hours they said they were shipping me a new unit. As long as a company stands behind their product when there is a problem, I will stand behind that company and support their product. I did install the new unit this past weekend (3/30/24) and it is working perfectly. I will add that the unit was very easy to install. ... show more
Reviewed in the United States on April 2, 2024 by Tom T

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