Someone was asking about how the engines power the gear box.
Source -
P&WC: PW206B2
Note the triangular flange that corresponds to the MGB input stage in previous post.
Source -
Pratt & Whitney: Media Library - Pratt & Whitney Canada
There are other good images of the fenestron tail rotor here including TR gear box and control rod etc
EC135
Edit: Turbomeca Arrius also power this aircraft.