meaning it has a set diameter

This non-polar

When replacing an existing unit

the TFDKR00 is built to withstand the mechanical stresses of commercial mechanical rooms

As the 632492R replacement part for the older 632492 model

Aaon P63270 Sensor/Electrode Els PW 17895 meaning it has a setThe Aaon P63270 Flame Sensor and Sparker Electrode is a critical combustion component designed for precise flame rectification and reliable ignition in high performance rooftop units and chillers. Engineered to withstand the thermal stresses of continuous burner operation, this dual function electrode ensures consistent HVAC flame sensing to prevent nuisance lockouts and HVAC ignition failure. As a direct OEM Aaon replacement part, the P63270