Sigh... I may have purchased the wrong heating pads. I hope not. Nothing in the product description says they have automatic shut off. The reviews said they don't have automatic shut off. The direction says, "If equipped with auto shut off, there will be a red LED light in the top left corner of the control." There is a red LED light on my controls... Went to the company website, no mention of auto shut off. Read more reviews. About 85% don't shut off, another 15% says they do. I have another hour to go to see if they shut off. DH insisted on going to the local farm supply store (30 miles on slushy, slippery, nasty roads) to buy a heat lamp bulb in case they do have the shut off. (I told him I could go after work tomorrow, but I think he was suffering from cabin fever.) Anyway, I'll let you know how it goes with the heating pads. The frames are built, legs on for adjustment, straw in the coop, waiting for babies on Wednesday. Will post pics of the MHPs soon, if they don't shut off on me...