I hope someone can help me with this project.
I need a very small switch device, no bigger than about 15 mm in diameter and up to say 25 mm thick, and powered by a small watch battery. The device would have one main function - when you press the switch, a light (say LED) flashes, at say 1 to 2 sec intervals for around 30 mins, then goes off. That's it. It would also be nice if it had a battery low function so that the LED would say flicker continuously for say 15 seconds if the battery was below a certain useable level.