Ducksback Forest Oak 5LDucksback Forest Oak 5L Product information You can apply this shed & fence treatment from the Cuprinol 5 Year Ducksback range to , using a brush or roller, to colour and provide protection. It takes 2 4 hours to dry and will cover up to 5m per litre on average. Colours & protects rough sawn wood Suitable for Wood Surfaces should be dry or slightly damp with no visible signs of surface water, & free from dirt, algae, lichen, fungi or moss. Features