Rifled copper tubing, enhanced aluminum fins. Downflow plates and manufactured housing drain hose and drain elbow included. Immersion tested at 500 psi, followed by nitrogen pressurization and factory sealing to ensure optimal system integrity and long-term reliability. Left-hand refrigerant/plumbing connections, with downturn suction line for easy installation in manufactured housing applications. Schrader provided for pressure assurance testing. Refrigerant and plumbing connections: Liquid line - 3/8" ODS, suction line - 7/8" ODS on 3-1/2 to 5 ton units. Drain connection: 177L pans have single LH 3/4" FPT. Heavy duty polypropylene drain pans. Includes Non-Bleed R-454B TXV - A2L refrigerants require a Refrigerant Detection System (RDS) for compliance.