The vents facilitate airflow from beneath suspended floors through the cavity. The units are adjustable vertically to extend through a number of brick courses. The front end of is designed to fit an Easy-Trim Air Brick Vent. If using horizontally, cavity sleeves should be fitted. The rear of the units feature a grille to prevent the entry of any vermin, large insects and debris that may cause blockages.                                                                  Details:                                                                       Colour: Black                                                      Material: Polypropylene