Filament Dryer Review
SUNLU FilaDryer S4 Review (2026)
Large dual-capacity dryer that fixes the #1 cause of failed prints: wet filament.
At a glance
| Category | Filament Dryer |
|---|---|
| Our rating | ★★★★⯨ 4.5/5 |
| Price | $60-80 |
| Availability | Check current price on Amazon |
| Returns | Standard Amazon return policy applies |
| Best for | Anyone printing PETG, TPU, or nylon, or in a humid climate. |
Our take
Wet filament causes popping, stringing, and weak parts — and PETG, TPU, and nylon all soak up moisture fast. The S4 dries up to two spools at once and can feed straight from the box while printing, so your filament stays dry end to end.
What we like
- Dries two spools at once
- Print directly from the box
- Big readable controls
- Fixes most 'mystery' print failures
What to keep in mind
- Takes up bench space
- Slow for very wet filament
- Fan is audible
Buy through Amazon and you're covered by their standard return policy. Check the live listing for today's price and real buyer reviews before you commit.
Sold on Amazon · Standard returns apply · Live price & reviews on the listing
Ready to look at SUNLU FilaDryer S4? Check current pricing, availability, and customer reviews on Amazon.
Check Today's Price →As an Amazon Associate, Print Gear Lab earns from qualifying purchases. Print Gear Lab is reader-supported. Some links on this site are affiliate links — we may earn a commission if you buy through them, at no extra cost to you. We only feature gear we'd recommend to a friend, and our opinions are our own.
Frequently asked questions
Is SUNLU FilaDryer S4 worth it?
Wet filament causes popping, stringing, and weak parts — and PETG, TPU, and nylon all soak up moisture fast. The S4 dries up to two spools at once and can feed straight from the box while printing, so your filament stays dry end to end. We weigh real-world usefulness against price, and we note the downsides honestly. Check the live price and recent customer reviews on Amazon before deciding — both can change.
Where can I buy SUNLU FilaDryer S4?
Through Amazon, where the standard Amazon return policy applies. We link to the current listing so you always see up-to-date pricing and availability.
Who is SUNLU FilaDryer S4 best for?
Anyone printing PETG, TPU, or nylon, or in a humid climate.
Is SUNLU FilaDryer S4 the best in its category?
It's one we think is worth considering, but "best" depends on your needs and budget — compare it against the alternatives in our reviews before you buy.