Panelised for 10x10cm size. Each board includes 3 wireless sensor boards (so you get 30 for your money!). They are easy to snap off but well attached to survive manufacture.
Designed specifically to fit in these project boxes:
There is also (just) room for a 2 x AAA battery holder in the box as well.
Simply add:
* Arduino Pro Mini
* XL4432 Radio
* 1 wire temperature sensor
* Some resistors (10k, 4k7)
* Power
And you have a sensor which can run for about a year from battery, uses off-the-shelf parts and costs very little.
Software (will be) available on github at https://github.com/8none1/