Cowled ventilation grille with anti-backdraught damper shutter PVC. For use with 100mm / 4 Inch diameter ducting. Concealed fixing points. Fixing screws / rawlplugs are not supplied with this item. Dimensions: 155mm tall x 155mm wide x 70mm projection. 99mm diameter spigot extends for 20mm. Fixing points 107mm horizontally / vertically.