Hi DMR
Thank you for your request.
The Saver Day Pass is valid from Domodossola or Chiasso to Lauterbrunnen. You have to buy a ticket to Chiasso or Domodossola, depending on the train you take.
You will find the information regarding Half Fare Travelcard on the following link. For more information, please contact our Railservice on +41 848 44 66 88 (CHF0.08/min.). If this number does not work, please try +41 51 225 78 00.
I wish you a good evening.
Regards
NicolasK