Medical FSA Approved underarm Children Thermometer, for Adults & Baby Digital Thermometer pad,Real-time monitoring APP tracking

I have recently decided to try out heat training, but I wanted to avoid paying an absolute fortune for the CORE body temperature sensor. I instead decided to give this a go: It is IP22 certified against water and dust, but I can also certify it against heavy sweating, at least after a few sessions. The app that is promoted with the product requires creating an account, and for some reason syncs everything to the cloud; I instead recommend using the Tempal app. The only problem I currently have is figuring out how to securely attach it to my armpit. I am using the heart rate monitor strap for now, but it only works as long as I am not moving too much. I also just ordered an elastic hand band, which is going to take some time to arrive, but I think it should work much better. In the meantime, do you have any DIY ideas for how to attach the thermometer securely to my armpit?