9.1
At a Glance
Filament dryerCategory
Multi-spool drying stationRole
70 CMax Temp
4 spoolsCapacity
YesPrint Through
NoVentilation
Best For
Multi-Spool PrintingNylon & TPUStringing PETGEnclosure Control
Pros & Cons
Pros
- Four-spool capacity makes it the cleanest single purchase for AMS-style benches, color swaps, and households with several open rolls.
- Active heat plus circulation solves the two-part drying problem: warming the spool and moving humid air away from the filament surface.
- Print-through workflow reduces the chance that a dried nylon, TPU, or PETG spool immediately reabsorbs moisture while a long job runs.
- The higher price is easier to justify when you would otherwise buy two single-spool dryers plus separate dry boxes.
Cons
- Overkill for a one-printer PLA bench where a sealed storage box and occasional single-spool dryer would do the job.
- Large footprint demands a real bench position, not a corner shelf.
- Multi-spool dryers do not replace labeled dry storage; partial rolls still need sealed long-term storage after the print.
Our Verdict
The SUNLU S4 is the best launch pick for a printer owner who has moved past one open PLA roll and now needs an actual humidity-control station. It is not the cheapest way to dry a spool, but it is the most coherent way to keep several filaments usable, print from the box, and stop treating wet PETG or nylon as a printer-tuning mystery.
| Full Specifications | |
|---|---|
| Category | Filament dryer |
| Role | Multi-spool drying station |
| Max Temp | 70C |
| Capacity | 4 spools |
| Active Heat | Yes |
| Active Airflow | Yes |
| Humidity Readout | Yes |
| Print Through | Yes |
| Ventilation | No |
| Resin Workflow | No |
| Abrasive Ready | No |
| Best Materials | PETG, TPU, nylon, PLA+ |
| Footprint | Large bench station |
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SUNLU S4 Four-Spool Filament Dryer
$169
Prices may change - check current Amazon listing.