This clever product combines an over fascia vent, a bird comb and an eaves guard to prevent rain from being blown up under the roofing membrane. Our 3 in 1 protection system comes in a 900mm length, and each length interlocks with the next. The eaves protector is nailed to the top of the fascia board, creating a continuous vent all along the length of the roof. It should be fixed at 300mm centres.Once nailed into position, the bottom of the felt is laid onto the top of the flat upward projection of the eaves guard.