ProMariner ProSport HD 20 Plus
#11 in 3 and 4 bankFull review
For bass boats with a starting battery and a 24 V trolling pair, with ignition protection for gasoline engine bays.
Amazon $255.63$255.63
The ProMariner ProSport HD 20 Plus rates 3.3 among 3 and 4 bank onboard marine battery chargers; the ProMariner ProSport HD 8 rates 2.9 among 1 and 2 bank ones. The ProMariner ProSport HD 8 costs $85.64 less ($169.99 vs $255.63).
ProMariner ProSport HD 8
#13 in 1 and 2 bankFull review
For a small boat with a starting battery and a modest trolling battery, from a maker whose chargers are built for engine compartments.
Amazon $169.99$169.99
Prices were last checked November 2, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Scores side by side
These two sit in different bank count classes (3 and 4 bank and 1 and 2 bank), and each is scored against the reference points for its own class, so a rating says how well each does among its own bank count peers. How we rank explains each factor.
| Factor weight | ProMariner ProSport HD 20 Plus | ProMariner ProSport HD 8 |
|---|---|---|
| Overall rating | 3.3/5 | 2.9/5 |
| Value 30% | 71 $12.78 per amp ($255.63, 20 A total) | 39 $21.25 per amp ($169.99, 8 A total) |
| Charge current 15% | 11 20 A total | 8 8 A total |
| Features 25% | 50 lithium mode, IP67 or better | 50 lithium mode, IP67 or better |
| Warranty 30% | 50 3-year warranty | 50 3-year warranty |
Specifications
| ProMariner ProSport HD 20 Plus | ProMariner ProSport HD 8 | |
|---|---|---|
| Charging | ||
| Banks | 3 | 2 |
| Total current | 20 A | 8 A |
| Lithium mode | Yes | Yes |
| AGM mode | Yes | Yes |
| Build | ||
| Water rating | IP67 | IP67 |
| Display or app | No | No |
| Ignition protected | Yes | Yes |
| Weight | 7.8 lb | 5.2 lb |
| Warranty | 3 years | 3 years |
| Released | 2021-01-25 | - |