1100 Series metal indoor 24 hour time switch. Automatic ON - OFF control when operation is required at the same time every day, 7 days a week. Automatic operation: Minimum ON setting: 20 minutes, Minimum off setting: 75 minutes. Temporary manual override: Standard. Operating temperature range: -40?? to +165??F.(-40?? to +74??C.) Metal NEMA 1 enclosure.