This hydraulic valve controls the flow of oil in the baler's tying or density system. It is installed in the main hydraulic circuit between the pump and the actuators that operate the knotter or the bale-chamber tension mechanism. A valve that leaks or sticks causes inconsistent bale density or missed knots. This original part is machined to the same spool-to-bore clearance as the factory assembly, which ensures the correct internal leakage rate for predictable timing of the hydraulic functions. On reinstallation, ensure the mounting surface is clean and the O-ring seal is replaced.