Buy a Twin wall flue kit online at the best prices and available for fast free delivery. Flue Direct established in 2001 is the leading supplier of flue and chimney products. These Complete Flue Kits are available in Black and stainless finish in 5 inch and 6 inch twin wall flue, push joint system for easy fitting and flush locking bands for a sleek finished look, Call, email or buy our Twin wall flue kits online HERE.