The Clik-R is an extremely versatile clicker. Created by world famous dog trainer, Terry Ryan, the Clik-R has an ergonomic design so that it fits comfortably in your hand. The raised button makes it easy to click; you can even put the Clik-R on the floor and click it with your foot. In addition, a stretchy finger strap on the back allows you to secure these clickers to your finger so that you never have to fumble around for your clicker or worry about holding onto it while you're trying to deal with treats and rewarding your dog. The noise the Clik-R makes is not too loud and not too soft. Size is 2.75" x 1.5". Loop on end allows you to attach to a key ring.