With this 13.5 tog all-season duvet, you're covered for year-round use. It comprises two layers of different weights, a 4.5 tog and a 9 tog duvet to use at different times of the year, then in winter you can tie them together to create a cosy 13.5 tog option. The soft duck feather and down filling gives natural insulation with a lofty, breathable feel, and corner poppers attach to our duvet covers to hold things neatly in place.