• Includes 4 one-way check valves of 12mm. • Built from durable, compact, and long-lasting plastic. • Medical-grade material, safe and non-toxic, suitable for water conduction systems. • Offers strong resistance to acids, alkalis, and salt corrosion, allowing use with various liquids. • Operates correctly at temperatures between -25°C and 60°C. • Designed to prevent reverse flow in fluid systems and in pneumatic systems for compressed air. • Applications in water treatment, air purification, automotive, industrial machinery, medical equipment, and household appliances.