SUNLU has announced the AMS Lite Heater, a $129.99 upgrade kit that bolts active drying onto Bambu Lab's AMS Lite multi-material system, letting owners dry filament and print with it at the same time instead of choosing one or the other. The accessory goes on sale July 20, 2026 at 07:00 UTC, and its rollout is timed to coincide with SUNLU's 13th anniversary, which the company is also marking with a 10,000-roll filament giveaway and an expanded U.S. factory footprint.
The pitch is narrow but pointed at a real annoyance. Bambu Lab's AMS Lite shipped without active drying or humidity control — spools sit exposed to ambient air, which is fine for PLA in a dry room but a liability for hygroscopic materials like PETG, ABS, ASA, PA (nylon) and PC in anything less than ideal conditions. SUNLU's kit retrofits that missing capability, according to both the company's own release and corroborating coverage from 3Dnatives, which frames moisture as one of the most common causes of stringing, weak layer adhesion, rough surfaces and inconsistent print quality in FDM printing generally.
What's Actually in the Box
The headline spec is a maximum drying temperature of up to 70°C, which covers the practical drying range for the six materials SUNLU lists as supported: PLA, PETG, ABS, ASA, PA and PC. That's a wide net for a single accessory — hygroscopic engineering filaments like PA and PC are far less forgiving of ambient humidity than PLA, so keeping them under heat throughout a print, rather than just before one, addresses a failure mode that pre-print drying alone can't fully solve.
SUNLU describes the heater as using a dual-airflow channel design for even heat distribution, paired with an automatic venting system that removes moisture from the enclosure during operation. Built-in humidity sensors monitor conditions inside the unit and can auto-trigger drying once moisture crosses a user-adjustable threshold, rather than requiring the user to manually start a drying cycle every time a spool goes in. SUNLU also lists integrated safety protections and temperature-monitoring systems as part of the package, aimed at preventing the kind of hot spots or overheating that can be a risk with any enclosed heating accessory bolted onto existing printer hardware.
The core functional claim — and the reason "AMS Lite Heater" is the right name rather than just "AMS Lite dryer" — is that none of this requires removing spools from the AMS Lite to dry them separately. Print-while-drying means the unit can maintain a print job's filament at drying temperature during active use, not just in an idle pre-conditioning cycle. That's the feature that distinguishes this from simply buying a filament dryer box and manually cycling spools in and out before loading them.
Why Bambu Lab Owners, Specifically
SUNLU designed the Heater around the AMS Lite rather than as a universal multi-brand accessory, which tracks with how SUNLU is positioning itself specifically within Bambu Lab's ecosystem rather than the broader third-party AMS market. The AMS Lite shipped without the active drying and humidity control of Bambu Lab's full-size AMS — a tradeoff that's tolerable for hobbyists running PLA in low-humidity climates and a real limitation for anyone printing engineering materials or living somewhere humid. SUNLU's kit is a direct attempt to close that gap without asking users to abandon the AMS Lite hardware they already own.
What It Means for Makers
For AMS Lite owners who have been fighting stringing or brittle layers — classic symptoms of wet filament, according to SUNLU's own materials — the AMS Lite Heater is a targeted, relatively affordable fix rather than a full hardware replacement. At $129.99, it avoids the workflow friction of pulling spools mid-print to dry them in a separate box, since drying happens in place while the AMS Lite keeps feeding the printer.
The materials list is the more interesting signal for makers pushing beyond PLA and PETG. Explicit support for PA and PC puts this squarely at users running engineering-grade filaments on consumer-class hardware, a segment that has grown as Bambu Lab's ecosystem has matured beyond beginner projects. If the auto-trigger humidity sensing works as described, it also removes a step that many users skip in practice — manually checking and drying filament before every print — by making drying reactive and continuous rather than a discipline the user has to maintain.
The caveats are the ones any pre-launch hardware announcement carries: independent reviews, teardown of the dual-airflow claim, and real-world drying-rate testing won't be possible until units ship on July 20. Neither SUNLU's release nor 3Dnatives' coverage details compatibility across different AMS Lite hardware batches, and neither source publishes independent third-party benchmarks of the claimed 70°C ceiling or the auto-trigger humidity threshold, so buyers should confirm fit with their specific unit before ordering rather than assuming universal compatibility.
Bigger Picture: SUNLU's Anniversary Push
The AMS Lite Heater isn't shipping in isolation. SUNLU is using its 13th-anniversary window — the company was founded in 2013 — to announce an expanded U.S. factory footprint alongside a giveaway of 10,000 filament rolls and 100 additional prizes to 100 winners selected across its platforms, positioning the company for faster domestic fulfillment and reduced dependence on longer international shipping times for its U.S. customer base. SUNLU cites more than 270 production lines, over 25 million products sold, and more than 530 intellectual-property rights secured as context for the anniversary push. Pairing a hardware launch with supply-chain investment suggests SUNLU expects sustained demand for AMS Lite accessories rather than a one-off promotional product, though how the U.S. expansion translates into pricing or availability for makers outside that anniversary campaign remains to be seen.
For now, the concrete facts are: a $129.99 accessory, a drying temperature of up to 70°C, support for six common filament types, and a July 20, 2026 on-sale date at 07:00 UTC. Makers running an AMS Lite in anything other than a bone-dry environment now have a purpose-built option to keep printing without the moisture penalty — assuming it performs as advertised once it's in hands.
