Extra Firm is the level of support to the body, suitable for extra heavily weighted people. This is not a comfort rating.
Open Coil are Bonnel springs in an hourglass shape, joined creating an open coiled mattress.
Fibre Fillings fillings are 100% polyester, man made, very durable, great recovery.
Mattress Depth 25 cm
Anti Allergy recommended, this mattress is suitable for allergy sufferers due to its fillings and fabric.