My intellitemp mats are about the same temp top and bottom and I just opened 3 unused zoo med spares and tested those and one was 12 degrees cooler on bottom another 17 degrees cooler on bottom and the last 13 degrees cooler on bottom. This was the reason I asked for the brand. I remember testing zilla, flukers, zoomed, Kane, intelltemp awhile back but couldn't find where I put my results so I decided to test a couple spares I had, unfortunately I don't have all the brands I had then. All these test I used 3 different temp guns to confirm Maybe this is the reason the thermostat let her hot spot get up to 111 degrees. Not only that but if you have a sensitive thermostat like a herpstat all it takes is a window open and cool air blowing over the exposed probe to raise the temps. This has happend a few times with my herpstat probe for the rhp when opening the cage or misting so I moved it and all is fine now. I have a dead zoomed uth I will be dissecting tomorrow to see if there is a reason the heat is more concentrated upwards instead of evenly both ways.