The Siemens 3RT1926-1CC00-ZX90 is an RC element surge suppressor rated for 48...127 V AC, designed to mount directly onto a Size S0 contactor. It suppresses voltage spikes from inductive loads — coils, contactors, relays — protecting nearby electronics and extending contact life. The pack delivers 10 units, typical for panel builders stocking spares for a line of contactors.
The 48...127 V AC range covers common control voltages in industrial panels — 48 V, 110 V, 120 V. The RC element is a passive snubber; it does not require a separate power supply. Mounting is mechanical to the contactor's coil terminals, so the fit is specific to Size S0 (Siemens 3RT1/3RT2 frame). If your panel uses a different contactor frame size, this suppressor will not clip on.