![Designer Marco Mattia Cristofori of the German 3D printer manufacturer BigRep, rides his nearly completely 3D printed e-motorcycle NERA, at the airfield Tempelhof in Berlin, Germany, December 3, 2018.(Photo/Agencies)](http://www.ecns.cn/hd/2018/12/05/9e0be86b4fa541999e0a92ea492a0480.jpg)
Designer Marco Mattia Cristofori of the German 3D printer manufacturer BigRep, rides his nearly completely 3D printed e-motorcycle NERA, at the airfield Tempelhof in Berlin, Germany, December 3, 2018.(Photo/Agencies)
![Designer Marco Mattia Cristofori of the German 3D printer manufacturer BigRep, checks a printed wheel of his nearly completely 3D printed e-motorcycle NERA in Berlin, Germany, December 3, 2018.(Photo/Agencies)](http://www.ecns.cn/hd/2018/12/05/66618a5672354e04959e17b2a313aa78.jpg)
Designer Marco Mattia Cristofori of the German 3D printer manufacturer BigRep, checks a printed wheel of his nearly completely 3D printed e-motorcycle NERA in Berlin, Germany, December 3, 2018.(Photo/Agencies)
![Designer Marco Mattia Cristofori of the German 3D printer manufacturer BigRep, stands with his nearly completely 3D printed e-motorcycle NERA, at the airfield Tempelhof in Berlin, Germany, December 3, 2018.(Photo/Agencies)](http://www.ecns.cn/hd/2018/12/05/3af6d2278c374ba59470d8f9543bc313.jpg)
Designer Marco Mattia Cristofori of the German 3D printer manufacturer BigRep, stands with his nearly completely 3D printed e-motorcycle NERA, at the airfield Tempelhof in Berlin, Germany, December 3, 2018.(Photo/Agencies)
![A 3D printer of manufacturer BigRep, which developed the nearly completely 3D printed e-motorcycle NERA, is pictured in Berlin, Germany, December 3, 2018. (Photo/Agencies)](http://www.ecns.cn/hd/2018/12/05/b24221edc2684eaf85af9b3d39a5c0ed.jpg)
A 3D printer of manufacturer BigRep, which developed the nearly completely 3D printed e-motorcycle NERA, is pictured in Berlin, Germany, December 3, 2018. (Photo/Agencies)