White Wavy Memory Foam Open Coil Mattresshis open coil spring mattress is a great value mattress that is hand made in the UK. Featuring a super soft cool touch top panel cover that is luxurious and comfortable. The mattress core contains a 13. 5 gauge patented ultra max diameter open coil Bonnell spring unit which distributes weight & pressure over a large area improving your sleep comfort. The mattress also consists of a layer of high quality open cell memory foam which shapes and adapts