The Duke (Firm). A Lavishly stuffed pocket sprung mattress with natural fillings. Silk, cashmere, wool and cotton are luxury fillings that you will only find at the top of the range. 2000 pocket springs make up the base, with great body moulding support and comfort. A 6 gauge rod edge combined with the British Bed Company's own Bulldog Border provides edge to edge support and minimises side-sag. So buy this The Duke (Firm) Was £649.00 Now £599.00.