Vial for fluid products with childproof system

A vial for fluid products comprising one of a pharmaceutical, a cosmetic, and a medical product, the vial comprising:

• a containment body provided with a dispensing mouth;
• a closing element that:
• in an initial configuration is joined to the containment body along a predetermined breaking line to close the dispensing mouth, and
• in an opening configuration, obtained by tearing the predetermined breaking line, is separated from the containment body to open the dispensing mouth;
• and
• an opening key that:
• in the initial configuration is slidingly fitted onto the closing element and rotationally released from the closing element, and
• in a working configuration is prismatically rotationally engaged with the closing element to put pressure on the closing element and remove the closing element from the containment body to obtain the opening configuration;
• wherein the closing element comprises an upper portion provided with prismatic protrusions interspersed with recesses, a central cylindrical element provided among the prismatic protrusions, and the opening key comprises a prismatic coupling seat with a bottom provided with prismatic protrusions interspersed with recesses, wherein in the working configuration the prismatic protrusions of the closing element are inserted into the recesses of the opening key, and wherein,
• the prismatic protrusions of the closing element and of the opening key are flared and widen at a base so that respective recesses narrow at the base.