Memory Foam Pillows have a technology produced by the use of polyurethane with additional chemicals which increase its viscosity and density. Memory Foam is often referred to as visco-elastic polyurethane foam. In some formulations, Memory Foam is firmer when cooler. Higher density Memory Foam Pillows reacts to body heat, allowing it to mould to a warm human body in a few minutes. A lower density Memory Foam Pillow is pressure-sensitive and moulds quickly to the shape of the body. Here at BedSOS.co.uk we supply a vast range of Memory Foam Pillows. We offer Next Day Delivery on all our Memory Foam Pillows (UK Mainland only).