Comparison : Item # SHT21NA, M1, 100 to 130 Volt (V) Alternating Current (AC) Voltage Shunt Release Trip (SHT)
Item # SHT21NB, M1, 220 to 240 Volt (V) Alternating Current (AC) Voltage Shunt Release Trip (SHT)
Item # SHT21NC, M1, 380 to 440 Volt (V) Alternating Current (AC) Voltage Shunt Release Trip (SHT)
Item # SHT21ND, M1, 480 to 500 Volt (V) Alternating Current (AC) Voltage Shunt Release Trip (SHT)
Item # SHT21NE, M1, 24 Volt (V) Direct Current (DC) Voltage Shunt Release Trip (SHT)