Features include:

Available for all Bosch Highflow appliances - 17E, 21E & 25E
Option of 3 Temperature Controllers: Main Controller (YPRM67XB), Bathroom Controller (YPRS67XB), Sub-Controller (YPRP62XB)
Digital Display Controllers - including time of day and water temperature
Unique Bath Filling function - alerts you when the desired volume and temperature is reached
Call Button on Controllers - for elderly or disabled requiring assistance in the bathroom
Constant Water Temperature - set and forget
Fault Diagnostic Display - in-built computer control checks functions and records any problems