Material - Made of quality PU and plastic. High pressure resistance, can withstand strong pressure without failure. Suitable for long-term use. Push-to-connect fittings type: 1/4 inch, 5/16 inch, 3/8 inch, 1/2 inch, compatible with 6mm, 8mm, 10mm, 12mm outer diameter tubes. Easy to use: Simple push-in design for connecting to the tube and provides a secure connection, no additional sealing required. Convenient: Quick connect fittings are easy to install, flexible, space-saving, and allow 360-degree rotation. Release rings feature an elliptical design for easy removal. No extra sealing needed—just a simple push for a secure connection. Application: Widely used in automatic production equipment across industries such as machinery, electronics, automotive, and packaging. Quantity: Package includes 40 pieces of fittings—10 pieces each of 1/4 inch, 5/16 inch, 3/8 inch, and 1/2 inch fittings—to meet various needs.