What is the Essential mattresses made of? OTTY 26 July 2019 13:20 Follow We’ll let this diagram of the layers do all the talking for us: Related articles Would you recommend using a mattress protector or a bed sheet? What is the Hybrid mattress made of? Has the foam used been tested to ensure it is safe? Can I use an electric blanket with my OTTY Essential? Comments 0 comments Please sign in to leave a comment.