Prepare for colder nights with our 13.5 Tog Duvet, crafted to provide maximum comfort and warmth. Available in Single, Double, King, and Super King sizes, it's the perfect winter essential for a cozy sleep. Duvets work by trapping warm air, and the higher the tog rating, the more warmth the duvet will provide. Also known as Corovin, the high tech manufacturing process produces a non-woven hypoallergenic fabric of unparalleled quality and strength. It has an extremely even web pattern and has equal strength in both directions. It is inexpensive and has the same warmth as an identical tog cotton quilt. It is strong, durable and lightweight.