Inner wall aluminum， outer wall galvanized for gravity draft venting of listed LP or natural gas burning appliances 100 million BTU per hours 500 degree Fahrenheit maximum appropriate for the wall where applicable not for wall furnaces boxed.

• Brand Name: Selkirk
• End 1 Diameter: 4 in.
• End 2 Diameter: 4 in.
• Adjustable: Yes
• Bend Degree: 90 deg
• Material: Aluminum
• Product Type: Stove Pipe Elbow
• Packaging Type: Boxed
• Vent Type: Type B
• Number: 4RV-EL90
• UL Listed: Yes
• Maximum Temperature: 500 �F