When ARB fitted my Safari snorkel they were reluctant to fill drain hole in base of airbox quoting several instances where vandals had poked a garden hose into top of snorkel on parked vehicles, filling the system with water then removing hose. With the drain unblocked they suggest that the water would soon drain away...with drain hole blanked it would be any expensive exercise for the unaware driver. Think I will be following austastar's suggestion and attach short length of hose then tuck it away when necessary.