Why buy me the sleepy moon mattress has traditional open coil springs for good postural support the removable top cover has coolmax technology to keep your baby cool and underneath is a practical waterproof layer that can be slept on whilst the top cover is being washed about me open coil spring continental cot mattress traditional mattress springs for good postural support comfort layer for gentle cushioning coolmax fabric technology to keep baby cool quilted removable zipped cover machine