- rigid plastic pieces in ABS or PLA - rubber outer print with NinjaFlex Water (semi-transparent) thermoplastic elastomer (TPE) filament. All parts are printable flat side down and without supports. NinjaFlex may be difficult to use on some printers. To address this we have been experimenting with casting the piece in transparent rubber. A complete set of instructions can be found on Instructables: http://www.instructables.com/id/IcosaLEDron-A-Multi-LED-Smart-Ball/