The H7732 series photosensor modules consist of a 28-mm (1-1/8") diameter side-on photomultiplier tube and a high-voltage power supply. These side-on photomultiplier tubes have long been used for spectroscopic applications and provide high gain and high sensitivity. Five types of photomultiplier tubes are provided as standard lineups to meet various needs for spectral response range. Connectors are used for power input and signal output. By selecting cables in convenient length, the H7732 can be easily installed inside equipment or removed from equipment. The H7732 is a general-purpose type and the H7732-01 is a low-noise type. The H7732-10 is sensitive over a wide range from UV to near infrared and has particularly high sensitivity in wavelengths above 600 nm. The H7732P01 and H7732P-11 are selected as low dark count types ideal for photon counting and low-light-level measurement.