Aspen 5 Ton Cased 3-Row A-Coil, 21 in, R-454B 20% Bleed TXV. Rifled aluminum tubing, enhanced aluminum fins. Embossed galvanized cabinets standard. Left- or right-hand refrigerant and plumbing connections. Upflow, horizontal right, and horizontal left without field modification—downflow application requires a field kit, sold separately. Split access doors in front of cabinet for easy service access. Fully insulated foil-faced insulation. Aspen A2L Refigerant Detection System Kits are available for R454B refrigerants, and are certified to meet the requirements of UL 60335-2-40. Add the RDS Kit, part # ASP-A2L4SA, to provide a complete installation of the required sensor and mitigation device required by the UL standard.