Cuprinol 5 Star Complete Wood Treatment is a clear, water-based, all-in-one wood preservative treatment for interior timber. Perfect for all interior timbers, including roof and floor joists, roof timbers, floorboards and more. It combines a woodworm killer, wet rot treatment and insect / fungus repellent all in one product. A clear, water-based, all-in-one wood treatment for interior timber Prevents insect attack, re-infestation and fungal decay Rids wood of wet rot, fungi and woodworm Deep penetration ensures effective treatment and lasting protection Low VOC