Abstract: A device for use in structures having masonry cavity wall construction for promoting removal of water and water vapor between a masonry exterior wall and a structural back-up wall. A plurality of the devices, which are elongated and have a generally “V” shape, are arranged in a systematic pattern in order to catch and retain trash mortar during a construction phase of the structure. Following construction, the device, which includes a wicking material to transport accumulated water beyond ends of the device, functions to promote the removal of water and water vapor in the cavity so as to prevent deterioration of the building materials of the walls.