Warning !!! In the product description, it says "2 versions: standard or FixPlus with Isofix connectors". This suggests that the product you buy works with or without Isofix. Not at all! This version is no isofix and can not be used with isofix.Il should have done a description difference with or without Isofix for 2 different products.
So I'll return the product ... it's not at all what I thought buying.