Ronseal Crystal Clear Outdoor Varnish is perfect if you’re looking to varnish wood and keep it’s natural colour. It’ll protect from the weather and doesn’t yellow over time like other traditional varnishes. Crystal Clear Outdoor Varnish is rainproof in 1 hour. Before you start make sure it’s a warm, dry day (above 10°c) and the wood is clean and dry, also make sure you wear a face mask to avoid breathing in any dust. Prep Stained or Varnished Wood: give the wood a good sand to make sure the varnish sticks. Then give it a clean with white spirit and leave to dry. Prep New Wood: give the wood a light sand, clean any dirt or dust with white spirit and leave to dry. You’ll need to put on 3 coats leaving 6 hours between coats. Before the final coat lightly sand the wood, this will help the varnish stick and give a smoother finish. Coverage: 16.0m² covered per litre.Number of coats: 3.Application: Brush.Drying Time: 1 hour.