The DuraPlus 6 Class A Chimney Pipe Wall Thimble adjusts from a minimum of 4 3?4 to a maximum of 7 3?4 wall thickness, and fits between standard wall studs. To accommodate thicker walls, the telescoping pieces can be extended up to 16 with a field-fabricated extension installed. Interior trim ring painted black. Must be installed with DuraPlus chimney pipe horizontally through the wall and extend a minimum of 2 into the room beyond the interior wall.ADA Compliant: No Collection: DuraPlus Depth: 4-3 4, 7-3 4 Fuel Type: Coal, Gas, Oil, Wood Length: 17 Material: Stainless Steel Pipe Class: Class A Pipe Inside Diameter: 6 Pipe Shape: Round Style: Functional UL Listed: Yes Vent Construction: Triple Wall Weight: 7 Width: 17