Norstar Key Service Units offer a full suite of different sizes to accommodate all small- and medium-sized businesses. Although discontinued in 1995 and replaced by the Norstar MICS, Norstar KSUs are still a good choice for cost-conscience businesses or for replacing a defunct unit.

Each KSU is distinguished by the number of lines it supports by the number stations, e.g. a 308 KSU natively supports 3 lines and 8 stations.

Norstar Key Service Units (308, 616, 824)