The ISM series of photoelectric amplifiers from Pantron are designed to provide optimum performance when used with Pantron photoelectric sensors in extreme and harsh environments. The ISM-4000 and the ISM-8000 offer carwashes the ability to connect multiple sets of photo eyes to one amplifier, which saves a carwash time, money and space. Use the ISM-4000 to connect up to four sets of photo eyes. Use the ISM-8000 when eight sets are needed. Expect zero possibility of crosstalk or interference between the sets of eyes.