The volume flow measurement funnel set is a practical accessory for precise measurement of air volume flows at ventilation outlets. It includes two funnel shapes - a round funnel with a diameter of 210 mm and a square funnel measuring 346 × 346 mm - which enable simple and precise adaptation to different air outlets. This set is ideal for use with the C.A 1227 thermo-anemometer from Chauvin Arnoux and supports reliable measurements during commissioning, maintenance and inspection of ventilation systems in building and air conditioning technology.