IoT Bolts
strainlabs.com
strainlabs.com
If you need that kind of thing, a wireless version would be great. I'm torn between kicking myself for not having thought of it and skepticism over the size of their market.
Here are their US patents: https://patents.google.com/patent/US10066930B2 https://patents.google.com/patent/US11149777B2
Could pose some organisations an interesting dilemma, where to draw the line for the extra expense.
A lot of the problem in IoT is that anyone who cares is already monitoring. So, you need to find someone who cares to implement monitoring, has money to implement monitoring, but doesn't already have monitoring in place. It's a small window.
Even worse, many companies who could benefit don't want to know. Knowledge brings certain legal liability--ignorance can be argued around.