{"product_id":"filament-dryer-box-s4-four-spool-3d-printer-dehydrator-rapid-heating","title":"Filament Dryer Box S4 Four-Spool 3D Printer Dehydrator - Rapid Heating","description":"\u003cp\u003eIn this review the Filament Dryer Box S4 is evaluated for makers and small print farms that need reliable filament storage and fast drying. The S4 stands out for its four-spool capacity and rapid, even heating driven by a 350W PTC heater and a three-fan layout. For those printing PLA, PETG, ABS or engineering filaments, the S4 combines practical humidity control with enough throughput to keep multiple printers fed, making it a useful tool for anyone frustrated by brittle or moisture-affected filament.\u003c\/p\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e350W PTC Heater:\u003c\/strong\u003e Delivers rapid heating up to 70 C so spools reach drying temperature quickly and reduce downtime between prints.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTriple-Fan Circulation:\u003c\/strong\u003e Three fans distribute heat evenly around all spools, lowering the risk of uneven drying or hot spots.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFour-Spool Capacity:\u003c\/strong\u003e Holds four 1kg spools at once with eight filament ports and PTFE tubes for simultaneous drying and printing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAuto Humidity Control:\u003c\/strong\u003e Built-in high-precision humidity sensor displays real-time levels and automatically activates at or above 50% to prevent reabsorption.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdjustable Timer and Temp:\u003c\/strong\u003e Temperature from 35 C to 70 C and timing from 0 to 99 hours with preconfigured presets for common materials for easier setup.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWide Filament Compatibility:\u003c\/strong\u003e Works with PLA, PLA+, PETG, TPU, ABS, PA, PC and standard diameters 1.75mm, 2.85mm and 3.00mm.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eWho It's For\u003c\/h2\u003e\n\u003cp\u003eThe S4 is best suited to hobbyists with multiple printers, small workshops, or anyone who buys spools in bulk and needs continuous access to dry filament. Its ability to hold four 1kg spools and feed multiple printers makes it a practical choice where throughput and storage matter.\u003c\/p\u003e\n\u003cp\u003eUsers who print only occasionally or only use one spool at a time may find the S4 larger and more powerful than necessary, and those seeking a completely silent solution should note the active fan system designed for even drying.\u003c\/p\u003e\n\u003ch2\u003ePros \u0026amp; Cons\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003ePros\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eLarge four-spool capacity that supports concurrent drying and printing for multiple machines.\u003c\/li\u003e\n\u003cli\u003eFast, even drying from a 350W PTC heater combined with triple-fan circulation.\u003c\/li\u003e\n\u003cli\u003eAutomatic humidity control with a live display helps keep filament ready for use without constant monitoring.\u003c\/li\u003e\n\u003cli\u003eSimple touch-screen operation with presets reduces setup time for common filaments.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCons\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eActive fans and a powerful heater mean it is not the quietest solution, which may matter in very noise-sensitive spaces.\u003c\/li\u003e\n\u003cli\u003eSome users report mixed durability experiences, so longer-term reliability can vary by unit.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003eHeater Power\u003c\/td\u003e\n\u003ctd\u003e350W PTC heater\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMax Temperature\u003c\/td\u003e\n\u003ctd\u003e70 C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSpool Capacity\u003c\/td\u003e\n\u003ctd\u003eFour 1kg spools\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFilament Diameters\u003c\/td\u003e\n\u003ctd\u003e1.75mm, 2.85mm, 3.00mm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eHumidity Control\u003c\/td\u003e\n\u003ctd\u003eHigh-precision sensor, auto-activate at 50%+\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTimer Range\u003c\/td\u003e\n\u003ctd\u003e0 to 99 hours\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFans\u003c\/td\u003e\n\u003ctd\u003eTriple-fan configuration for even circulation\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch2\u003eOur Verdict\u003c\/h2\u003e\n\u003cp\u003eThe Filament Dryer Box S4 is a strong choice for users who need to dry and store multiple spools reliably; its \u003cstrong\u003efast heating\u003c\/strong\u003e, triple-fan circulation and automatic humidity control deliver consistent filament condition and improved print quality. For workshops and multi-printer setups it represents good value, though those needing a quieter or smaller unit should compare alternatives.\u003c\/p\u003e\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eCan it run while printing?\u003c\/strong\u003e\u003cbr\u003eYes, the S4 supports feeding filament through PTFE tubes and eight ports so multiple printers can draw filament while the unit maintains drying and humidity control.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat filaments are compatible?\u003c\/strong\u003e\u003cbr\u003eThe unit is compatible with PLA, PLA+, PETG, TPU, ABS, PA, PC and other common 3D filaments at 1.75mm, 2.85mm and 3.00mm diameters.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eHow does the auto humidity feature work?\u003c\/strong\u003e\u003cbr\u003eA built-in high-precision sensor displays interior humidity and automatically starts the dryer when the level reaches or exceeds 50% to prevent moisture reabsorption.\u003c\/p\u003e","brand":"YOOPAI","offers":[{"title":"Default Title","offer_id":48194141946075,"sku":"B0F29D35JQ","price":149.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0724\/1043\/1707\/files\/61ZuWFZOvCL._AC_SL1500.jpg?v=1770236647","url":"https:\/\/gearmusthave.com\/products\/filament-dryer-box-s4-four-spool-3d-printer-dehydrator-rapid-heating","provider":"GearMustHave","version":"1.0","type":"link"}