The product is a pack of 12 pneumatic push in fittings designed for connecting air or water pipes with a diameter of 4mm. These straight connectors are ideal for use in hydraulics, pneumatics, pumps, and plumbing systems. The fittings offer a secure and reliable connection for efficient transfer of fluids. Perfect for various industrial and commercial applications, these pneumatic push in fittings provide a convenient solution for connecting pipes and tubes smoothly.