Sentinel Federal Credit Union ← View details 22752, Mule Deer Trail, Box Elder, SD 57719 +1 605-923-1405 sentinelfcu.org Suggest an Edit Name* State* Locality* ZIP* Street address* Phone* Website Opening hours Monday: 08:00 am — 05:00 pm Tuesday: 08:00 am — 05:00 pm Wednesday: 08:00 am — 05:00 pm Thursday: 08:00 am — 05:00 pm Friday: 08:00 am — 05:30 pm Your comments * — Required information