The Silentnight 800 Mirapocket Mattress is a medium-firm mattress made using sustainable Eco Comfort Fibresâ„¢. It features 800 individual Mirapocket springs zoned to support your body at key points. The highly breathable Eco Comfort Fibresâ„¢ help keep your mattress feeling fresh. This mattress is made in the UK and includes a 5 Year Guarantee for your peace of mind. It is designed to absorb movement, helping you sleep soundly even if your partner shifts. The mattress has a soft, hypoallergenic knitted cover and is single-sided, requiring rotation every few months.