Gralab 555 Electronic Digital Switching Timer

Replacing the 545/645, the 555/655 are ready to go to work for you. These timers are excellent performers for timing kinetic experiments, start and stop times for gas chromatography, safety shutoff on critical equipment, centrifuges, x-ray equipment and quality control analysis. The 555/655 have an instantly repeatable time cycle, and these digital circuits react little to power line interference and none to frequency variations.