Laboware is presenting the product best in quality & make by laboware.The apparatus is designed to determine, the Stefan Boltzmann constant. The apparatus consists of a hemisphere fixed to a Bakelite plate, the outer surface of which forms the jacket to heat it. Hot water to heat the hemisphere is obtained form a hot water tank, which is fixed above the hemisphere. The copper test disc is introduced at the center of hemisphere. The temperatures of hemisphere and test disc are measured with the help of temperature sensors.