Steel with standard type teeth 104 BCD
4-arm 104-BCD spider bolt-on fitting.
These hard-wearing E-bike suitable chainrings are designed for normal loads encountered in the E-bike leisure sector. 
Wippermann utilises the processes established in their industrial sector for hardening the Connex chainrings, as well as the particularly high-performance cathodic dip coating. Specially developed for the high loads caused by e-bike drives, they are compatible for use with all common drive systems from Bosch, Yamaha, Brose, Bafang and many more. Of course, those bikes powered by human muscles can also benefit from using steel Connex super-hard wearing, high-performance chainrings.
Technical details
Material: hardened Steel with Black KTL-coating
Tooth profile: Standard (flat), 1 1/128" (Narrow) 
Spider fitting: Bolt circle diameter (BCD): 4x104mm
Suitable for use on Bosch, Yamaha, Brose, Bafang and other systems
Sizes: 32, 34, 36, 38, 40, 42 and 44 teeth
Suitable for: 1/2" x 3/32" and 1/2" x 11/128"