This is a fantastic little item, only a few centimetres long and a few millimetres thick. Unlike some other third-party camera remotes, it isn't cluttered with lots of unnecessary buttons for other makes of camera. It has one button which, on my Pentax K-X, can be used to release the shutter immediately or after a 3-second delay, both with or without autofocussing before releasing the shutter (actions are configurable within the camera menus). The lithium cell is easily replaceable. Delivery by CameraMarket UK was very prompt. Excellent.