Comfortable Foam Sleep Silentnight. The Comfortable Foam Sleep is made with a high density of Miratex foam. This foam will absorb your movements and relieve tension whilst eliminating any roll together or roll off. The mattress is made with a soft-touch knitted cover plus it is completely hypoallergenic and dust mite resistant. Please note: this mattress is not suitable for use on tubular steel slats. Cover may vary. So buy this Comfortable Foam Sleep Silentnight Now £115.00.