Temperature Sensor Clamp for Homemade Lab Incubator

My grand niece needed a temperature-controlled little incubator for science projects but most are too big and too expensive. The small ones seem to be designed for eggs. I was looking at various boxes and heaters to use and stumbled across the Hot Logic Mini Personal Portable Oven for $45 at various online outlets. It’s a small, insulated, box-like, zippered, soft container with a 110 volt hot plate that is just powerful enough to heat a lunch or dinner in a few hours. I then found a simple on/o