The natural solution to stiffen up your hammock mattress and make the hammock base flatter and more open, this 75cm long by 27 cm wide 2cm thick insert is made of coconut fibres formed into a firm and partly flexible sheet with natural latex. It is used by our mattress makers at InNature for a structured, breathable layer, and will hold its shape over time. Must be used with our natural wool mattress or mattress protector on top.