This emergency style button can accomodate a wemos mini D1 with battery shield and a li-ion battery 18650, 3350mAh. A simple push button is added in the center piece. The button type is as seen in picture. Everything is screwed together. No glue needed, so all parts can be detached again. Wires from wemos to button need to be soldered ofc. The red cap needs to accomodate a spring in the center. You will have to slide the spring over the rectangle from the central cylinder. A micro usb female to male extension cable is inserted so that you can easily recharge the battery, without reopening the case. I'm using this setup as an amazon dash button clone. When pressed, my wemos wakes up from deep sleep, connects to wifi, sends an mqtt message and goes back into deep sleep. 60 days of autonomy when button is pressed three times a day. Button measures 86x86mm, case is 30mm high, with button height is 60mm.