HEAT HOLDERS Men's Plain Ribbed Knitted 3.4 tog Thermal Winter Beanie Hat Grey Outer: 53% Polyester 47% Acrylic, Lining: 100% Polyester Heat Holders hat with furry brushed lining 3.4 Tog rating for extra warmth Chunky rib Heat Holders 3.4 Tog Hat is exceptionally thermally effective, with a new Heatweaver plush insulating liner that has been developed to hold even more heat in. Keeps you warmer for longer A super gift!