The container for containing a product, typically cosmetic, has an internal receptacle mounted in an external covering receptacle, by using an adapter insert. The receptacles are made of glass and an attachment region is provided internally on the internal receptacle, near its annular upper end, in order to secure the latter to the insert. The insert is provided with an insertion portion received internally within the external receptacle, a first locking unit and second locking unit. The first locking unit, formed in an elastically deformable portion separated from the rest of the insertion portion by slots are opposing the rotation of the insert around the internal receptacle, while the second locking unit is opposing the rotation of the external receptacle around the insert by engaging on a neck of the external receptacle.