Aluflex Aluminum Semi-Rigid Flexible Bare Duct
Aluflex Semi-Rigid Duct is made out of aluminum and can be bent to allow for curves and offsets in the duct run. While it is best to use rigid duct from the dryer to the wall termination, clearance issues may require the use of semi-rigid duct.
Semi-rigid duct may also be used as a temporary connection until you can install a rigid duct. It is a much better choice than flexible ducting as it will not collapse on itself and the inside is smoother which prevents trapping and buildup of lint that may affect the airflow quality.