Osmo UV Protection Oil Extra 420 2.5Ltr Free Next Day Delivery!! (If ordered before 2:30pm) Osmo UV Protection Oil Extra 420 is especially recommended for the treatment of timber cladding, roof overhangs, balcony elements, garden furniture, windows and doors etc. Key Benefits: • Protects the wood against mildew, algae and fungal attack • Maximum 2 coats on raw wood, 1 coat for renovation applied to a clean and dry surface. • 1L covers approx 24m2 per coat.