The incubator I just picked up this morning has a hole drilled in the side and was supposed to have a set mounted on a bracket that attaches through the hole. Needless to say, it wasn't there. Eventually I'll get a replacement I think.I have used cheap and expensive and all that pet smart had to offer. I have lost a lot of hatches in the process.... I only use the gqf thermometers that stick into the cabinets for the thermometers and use another one with a wick on the end for the hygrometer. It has perfect readings everytime. All the others you have to re-calibrate constantly and I don't have patience or time to do that. Old fashioned in this case works much better than anything else you can buy.