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ProMariner

ProMariner 44021 ProSport HD Waterproof Marine Battery Charger, 20 Amp, 3 Bank

  • Based on 799 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon
Arrives Saturday, Aug 8
Order within 11 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


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


Color: Gray/ Yellow


Brand: ProMariner


Mfr Part Number: 44021


UPC: 031669440210


Manufacturer: ProMariner


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: Saturday, Aug 8

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
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • Zip Pay in 4
  • Financing through Apple Pay
  • Financing through Google Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Charged
Pattern Name: Charger Style: 12/24/36V, 20 Amp, 3 Bank
Worked great. Easy to install. Fit perfect
Reviewed in the United States on April 13, 2026 by CDG_BMW
    • 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
    • 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
    • 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
    • Charger
Pattern Name: Charger Style: 12/24/36V, 20 Amp, 3 Bank
Have had this installed on my prov for over 5 years and it has worked flawlessly. Plug it in and always now you are going to have fresh batteries when I hit the water. I also live in a climate were-20f is common in the winter, I leave my batteries in my boat plugged in during the winter and this unit keeps my gel batteries in great shape all winter ... show more
Reviewed in the United States on January 25, 2025 by Kbolt
    • Not Working
Pattern Name: Charger Style: 12/24/36V, 20 Amp, 3 Bank
Seem to work couple months I have installed. Stopped working and opened it up. The unit was full of water. Must’ve got a little water on it and sucked it right in. I guess the heating in the cooling of the other unit and the moisture in the engine compartment, allowed it to draw it in, but it’s not working anymore. No way of contacting the seller to return it seem to be quality product and work but quite expensive for only four months ... show more
Reviewed in the United States on November 9, 2025 by John Hutson
    • 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
    • Super Impressed
Pattern Name: Charger Style: 12/24/36V, 20 Amp, 3 Bank
Unit is great in appearance! Operates as advertised. Found and isolated a defective battery in my boat right away. So far, an impressive unit!
Reviewed in the United States on June 17, 2025 by Tom Rust

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