Always see it in English
It is a price set by Reference Reseller Companies and you can find out what it is beforehand. Once contracted it is fixed for 12 months.
This price may be more expensive but you know the price you are paying, so changes in your bill will depend only on how much you use.
After the 12-month period the price may vary and to renew it you need to apply for it again. The Fixed Price of all Reference Reseller Companies is posted on the National Commission of Markets and Competition website.
Thus this option means: