The Pensky Martens Flash Point Apparatus is an instrument used to determine the flash point of a flammable liquid. It is used to assess the flammability of liquids by measuring their auto-ignition temperatures. The apparatus consists of a test cup and a heating device, typically an electric heating element, that is used to heat the test cup containing the liquid sample. The test cup is closed with a lid to prevent evaporation of the liquid sample and to ensure that the temperature remains constant. As the temperature rises, the flash point is reached when the liquid vaporizes and a spark is released. The flash point is recorded and the apparatus is then shut off.