Flex TPU 85A Filament - High Flow, ISO 10993 Tested (1kg)

In this review of Siraya Tech Flex TPU 85A filament, the bottom line is clear: this spool is ideal for makers who need a balance of high flexibility and reliable toughness for wearable or soft components. The reviewer found the filament especially useful when printing flexible prototypes like custom footwear soles and protective gear because the material stretches without tearing and prints faster than many stiffer TPUs. The included moisture-resistant aluminum resealable bag also stood out as a practical feature that protects filament quality between uses.

Key Features

• Superior Flexibility & Toughness: The filament produces pliable, durable parts that hold up to bending and repeated use, making it suitable for flexible end-use items.
• ISO 10993 Tested: Testing to ISO 10993-10, -5 and -23 provides useful biocompatibility data for externally worn items and helps reduce uncertainty for wearable prototypes.
• High Flow, High Speed: Formulated for higher flow, this TPU prints faster than many 95A alternatives while maintaining good surface finish when used with a direct drive extruder.
• Moisture-Resistant Packaging: The resealable aluminum bag limits water absorption and preserves print consistency for long storage, supporting up to three years shelf life.
• Wide Compatibility: The 1.75mm filament works with most 3D printers that handle flexible materials, offering reliable extrusion across a range of setups.

Who It's For

The filament is best for hobbyists, small-batch manufacturers and designers who need a soft, resilient material for items like custom footwear, phone cases, or protective gear. Its ISO 10993 testing makes it appealing to those prototyping externally worn devices or parts that contact skin.

Beginners can use it, but users who prefer very rigid, high hardness materials or who cannot tune printer settings for flexible filaments should look elsewhere; optimal results come from machines with a direct drive extruder and some tuning to reduce stringing.

Pros & Cons

Pros

• High flexibility and toughness deliver durable, bendable prints for functional parts.
• ISO 10993 testing supports use in externally worn applications where biological response data is helpful.
• High-flow formulation speeds up printing compared with stiffer TPUs while keeping good print quality.
• Resealable aluminum bag helps prevent moisture uptake and extends shelf life.

Cons

• Some users report mixed results on stickiness to tubing and occasional stringing, so extrusion tuning may be needed.
• Optimal performance is recommended on direct drive extruders, which limits ease of use on some Bowden setups.

Specifications

Our Verdict

Siraya Tech Flex TPU 85A is a strong choice for users who need a fast-printing, highly flexible filament with documented biocompatibility testing and durable packaging. It represents good value for prototypes and small runs of wearable or protective parts, provided the printer is set up for flexible, high-flow materials.

Frequently Asked Questions

Is this filament safe for wearable prototypes?
The filament has ISO 10993-10, -5 and -23 testing data, which helps assess biological responses for externally worn items.

What extruder works best?
A direct drive extruder is recommended for optimal flow and reduced feeding problems when printing this flexible filament.

How should the filament be stored?
Keep it sealed in the included moisture-resistant aluminum bag when not in use to preserve print quality and shelf life.