A respiratory treatment device comprising at least one chamber, a chamber inlet configured to receive air into the at least one chamber, at least one chamber outlet configured to permit air to exit the at least one chamber, and a flow path defined between the chamber inlet and the at least one chamber outlet. A restrictor member positioned in the flow path is moveable between a closed position, where a flow of air along the flow path is restricted, and an open position, where the flow of air along the flow path is less restricted. A vane in fluid communication with the flow path is operatively connected to the restrictor member and is configured to reciprocate between a first position and a second position in response to the flow of air along the flow path.