Callaway Series Home / Our Specialties / Fireplaces / Gas - Linear / Callaway Series Callaway 40 Viewing Area 40”W x 13”H BTU 31,500 - 16,500 Heating Capacity Fuel Type Gas Callaway 50 Viewing Area 49-7/8”W x 13-3/8”H BTU 35,500 - 18,500 Heating Capacity Fuel Type Gas Callaway 50 See-Thru Viewing Area 49-7/8”W x 13-3/8”H BTU 35,500 - 18,500 Heating Capacity Fuel Type Gas Callaway 72 Viewing Area 72-7/8”W x 15-3/4”H BTU 49,500 - 25,000 Heating Capacity Fuel Type Gas Heat Management Komfort Zone Kit Vented Cavity Heat Transfer Kits Faces Mission Rectangle Four Pieces Rectangle One Piece Gallery Liners Black Glass Herringbone Ledgestone