Product review (1 stars): Make sure to check if this is legal where you live
The plumber I had install my washer/dryer he had to use a different vent duct as product is no longer legal in Massachusetts due to its cheap construction and how easily it tears.  I'm guessing that this is the case is at least a handful of states in the US so I would recommend shelling out a few extra dollars and getting a semi-rigid aluminium duct.