An easy drop in for an RV that already has a WFCO 9800 deck mount, with lithium detection built in. A safe default for a typical trailer.
Amazon $248.99The WFCO WF-9855-AD rates 3.2 among standalone RV converter chargers; the Progressive Dynamics PD4655V rates 2.4 among panel and drop-in ones. The WFCO WF-9855-AD costs $55.22 less ($248.99 vs $304.21).

A proven fix for a dead converter in an older Parallax, Magnetek or WFCO power center that still runs lead acid batteries.
Amazon $304.21Prices 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 build classes (standalone and panel and drop-in), and each is scored against the reference points for its own class, so a rating says how well each does among its own build peers. How we rank explains each factor.
| Factor weight | WFCO WF-9855-AD | Progressive Dynamics PD4655V |
|---|---|---|
| Overall rating | 3.2/5 | 2.4/5 |
| Value 35% | 34 $4.53 per amp ($248.99, 55 A) | 22 $5.53 per amp ($304.21, 55 A) |
| Output 10% | 50 55 A | 50 55 A |
| Features 30% | 80 lithium mode, multi-stage charging, fan runs only as needed | 20 multi-stage charging |
| Warranty 25% | 25 2-year warranty | 25 2-year warranty |
Specifications
| WFCO WF-9855-AD | Progressive Dynamics PD4655V | |
|---|---|---|
| Charging | ||
| Output | 55 A | 55 A |
| Lithium mode | Yes | No |
| Multi-stage charging | Yes | Yes |
| Build | ||
| Build | Standalone | Panel or drop-in |
| Fan runs only as needed | Yes | - |
| Remote or display | No | No |
| Weight | 5.5 lb | 10 lb |
| Warranty | 2 years | 2 years |