Hi Rania, 
 
Thanks for your question. 
 
We don't manufacture or retail an extra firm latex mattress. We have our Fusion range of mattresses, consisting of 100% natural latex. This range gives a cool sleep surface whilst also having a similar sink in sensation to memory foam but without the heat issues associated.
 
The Fusion 6 is our firmest mattress within that range, simply consisting of an 80KG Firm density core mattress. 
 
For you at 55kg this will feel firm in the comfort and for your husband at 90kg it will feel firm but slightly softer due to the differing weights. 
 
Please see below for the full breakdown of the Fusion 6 model;
 

 
We are an online only retailer so all orders need to be placed via the website. A King Size Fusion 6 is currently £1150.00. Being an online only retailer this is the main reason we have our 60 day love it or return it guarantee. This is a no quibble policy meaning you can send the item back for a full refund if unsuitable or you can utilise the one time exchange to swap to a different product. We would never leave you with a product that isn't right, whatever the reason might be for that. 
 
I hope this has answered your questions fully but if you do have any further queries please don't hesitate to contact our office on 0161 437 4419.
 
Kind Regards, Lee.