Cuprinol woodworm killer wb kills all types of wood boring beetle larvae its deep penetration ensures effective protection for years to come this low odour water based formula has been specially developed to make it more pleasant and convenient to use application bare wood flood surfaces with 2 or 3 brush coats pay particular attention to endgrain corners joints crevices etc in severe cases also inject into flight holes 7 10cm 3 4ins apart and repeat treatment re treat surfaces cut after treatme