On this page, you are looking at the Diode Dynamics Wiring Harness. This wiring harness is available for separate purchase and has been designed to allow your C-Lights to work as daytime running lights as well.
Here are the details:
Allows C-lights to work as daytime running lights while deactivating the factory DRL
Specific for the 2015+ WRX / STI with the Diode Dynamics C-Light
Complete with (1) module and harness to control both sides of the vehicle