I have grown even the cadence sensor 00425 and am very satisfied.
The backlight can turn though, this goes but by itself quickly again. It is activated by a short keystroke. A continuous lighting is probably to preserve the battery unfortunately not possible.
So who needs accessories for this thing and do not know if it fits, here my working combination:
Tacho 16:12
Universal holder for Type 00428 second bike
Cadence Sensor Sigma type 00425