Slot Ventilation Diffuser Ergovent Lineo 600 (2 x 75 mm Duct Conections 1 Slot x 600 mm x 20 mm With Damper) AX3607 H16 models are only 16cm H16 models are only 16cm deep so perfect for tight ceiling voids and can be used in either a ducted or recirculating configuration (with the addition of the optional recirculating kit available by following this link) reliable temperature probes (type K thermocouple) in the "Probes" tab Duct connection box has antistatic and antibacterial properties Diffuser made of recycled material with similar material properties to plasterboard (eg expansion and contraction) to eliminate risk of cracks forming in final finishes