Fenner Drives, a division of Fenner PLC, has entered the FFF/FDM 3D printer filament market with NinjaFlex™, a highly elastic flexible filament available in both 1.75 and 3.0 mm diameters. The company is known for its production of power transmission components such as drives, belts and bushings, and has a history of materials development experience.

NinjaFlex is a patent pending thermoplastic elastomer (TPE), an elastic polymer with rubber-like properties similar to compounds commonly used for seals and molded flexible parts in daily applications. It comes in four colors and is designed to be extruded at temperatures between 210°C and 225°C onto a platform of 30°C to 40°C.

It is preferable to use an extruder incorporating a spring loaded roller bearing that applies pressure against the drive gear. Due to its flexibility, the filament should be supported between the drive gear's entrance and the melting chamber. Fenner Drives lists the following as an example extruder type: http://www.thingiverse.com/thing:147518.

It is not necessary to treat the build platform for adhesion. NinjaFlex bonds well with surfaces such as aluminum and glass. The material does not contain BPA or other toxins, but it is not recommended for food contact applications.


  • Filament shore hardness of approximately 85A
  • Consistent diameter and material properties provide reliable, high quality prints
  • Patent pending technology allows for smooth feeding
  • Low tack, low CoF exterior allows smooth feed through filament guides
  • High elasticity and excellent abrasion resistance
  • Excellent build platform adhesion and bonding between layers
  • REACH and RoHS 2002/95/EC Directive Compliant
  • 1.75mm filament spool = .50 kg
  • 3.00mm filament spool = .75 kg

NinjaFlex is available on the Fenner Drives web site, priced at $49.92 per 1.75 mm spool and $59.96 per 3 mm spool.