Reefwalker, you know you are here in a DIY section.
Many people here are bored to pay a lot of money every time it is a question of materiel of dive or underwater photography.
As well made is your material, i think 70$ is too much for just a board, a transistor, a buzzer and a cell.
Many thank for guys like Hanachan and others to show us how to save money !
You may notice it wasn't me that started this thread!
I was simply clarifying that my Leak Detector doesn't consist of US$3 worth of material. It also isn't a board, a transistor, a buzzer and a cell. It's actually a whole lot more than this! Plus not everyone is handy with electronics and soldering etc. so these people can buy a pre-made item and fit it themselves.
I think its great that this DIY forum is here for people to save money by doing it themselves. I am a DIY guy myself. Which is how I came to manufacture the Leak Detector. I made one for a friend and then one for myself. Now I've made hundreds for other happy customers around the World who want a fit-yourself Leak Detector that costs a whole lot less than some of the housing manufacturers charge for the 'genuine article'.