The 4Poly Flow-4BKHD Compress Str from Fittings Unlimited Inc is a compression straight fitting designed for efficient fluid transfer in poly piping systems. With a 4mm size, this fitting ensures a secure connection that prevents leaks. Made from durable materials, it is built to withstand pressure and resist wear. The design allows for easy installation and compatibility with standard poly piping, making it a versatile choice for various applications. This fitting adheres to industry standards, ensuring reliability and safety in your plumbing systems.