MRCOOL H4TXV02 Signature Series 3 to 3.5 Ton TXV Kit is a thermostatic expansion valve assembly designed to regulate refrigerant flow in compatible HVAC systems. It works by sensing evaporator outlet temperature and adjusting refrigerant flow to maintain proper superheat, supporting efficient heat transfer and compressor protection. Designed for use with compatible MRCOOL 3 to 3.5 ton... https://www.partshnc.com/mrcoolr-signature-series-txv-kit-h4txv02