This model provides the same features as the T170 Series Skipper models for omitting operation on selected day(s) of the week. The T170CR series also provides a minimum of 16 hours of carry-over for maintaining preset schedules during power failures. The carry-over automatically rewinds when power resumes. Only one hour is required to rewind the carry-over for each two hours of power outage. All models are equipped with one CUTOUT tripper (which also serves as "ON" tripper) one "OFF" tripper and three skipper screws.