Duck Feather all seasons single duvet is a combination of a 4.5 tog & a 9 tog duvet which can be used separately in warmer months & fastened together for a 13.5 tog winter duvet.[br] The duvets are filled with 85% white duck feather & 15% white duck down for added softness & warmth. The individual pocket construction eliminates cold spots & the need for daily shaking, ensuring the filling remains in place.[br] The natural fill duvets have 100% cotton percale cover for breathability & softness.