HANGABLE CLASSIC SKEEWBACKERSTM - 1/2"
Hangable Skeewbacker Classic 1/2 in. mosaic backers are designed to have a hanging system installed directly to the backer. One is available or you can make your own. There are 11 sizes to choose from. They are constructed from a rigid polystyrene foam core sandwiched between waterproof membranes.
see this short video on installing the hanging kit