Packaging device for a product to be dispensed

A packaging device for a product to be dispensed, comprising:

• a bottle suitable for containing the product to be dispensed and having a neck comprising an inner wall delimiting an opening,
• a dispensing device comprising a body and suitable for dispensing said product,
• a fastening element for securing the body of the dispensing device in the neck of the bottle, the fastening element cooperating with the inner wall of the neck of the bottle,
• wherein the fastening element comprises a cylindrical double wall comprising an outer wall and an inner wall forming an internal hollow shaft, said outer and inner walls being coaxial, and
• wherein said dispensing device comprises a fastening member of said dispensing device, the fastening member being integral with said dispensing device and being fixed around the internal hollow shaft of the fastening element.