This relates to only some of mattresses for sale at Bed Kings, which will be discussed and offered at point of sale. You must purchase a mattress protector from Bed Kings and use at all times on new mattress. Also as part of the guarantee you will be required to pay for the delivery charge to swap over the new mattress. We suggest you give your new mattress at least 30 days trial prior to considering a swap. If you decide to change, you need to come to the store and select a new comfort choice. Once you have chosen we will schedule a new mattress to be delivered and swapped with your existing mattress.