A Preformed duct designed to replace a perpendicular mortar joint and to allow water gathered by cavity trays and DPC's to be discharged through the outer leaf and also to provide ventilation.
To be installed at maximum 1 metre centres (i.e. every fourth perpendicular joint to comply with building regulations. BS5628 part 3  and BS8215. When working to NHBC standards, install at maximum 450mm centres (ie. every other perpendicular joint).
 
Colours: Red, Buff, Black, Grey, White and Clear.