Coin pinger is very easy to use, comes with wooden small stick. To test a coins with a smart phone as shows on the picture you need to download app: coin ping test. To test a coin you need to place a coin on the center so coin well not touch the body of the pinger only pinch points and gently hit a coin with the small stick around the smartphone and app will show the test result . Coin pinger is made of soft plastic need to be clean and free of dirt and dust to be safe to use for best results.