The ZoneFirst PIRR is a 24Vac 4PDT Plug-In Relay engineered as a direct high-performance replacement for RR and RMABS relays

extending the functional life of the contacts

High-Durability Construction: Materials selected for resistance to corrosion and structural fatigue in outdoor refrigeration systems

these units are typically tested for higher proof pressures

638-inch ID

Siemens Industrial Controls 3RH2921-1DA11 Switch R-410A The ZoneFirst PIRR is aThe Siemens 3RH2921 1DA11 is a high performance lateral auxiliary switch block specifically engineered for the expansion of control circuit contacts. Designed for veterans in the field, this Sirius auxiliary contact features a robust 1NO + 1NC (1 Normally Open and 1 Normally Closed) configuration, providing essential feedback for motor control logic. Its side mount architecture allows for a space efficient 10mm profile, attaching seamlessly via snap