Hydraulics Spare Parts Hydraulics Spare Parts supplier at Sonu Hose Pipe Mayapuri New Delhi . Top Left (Silver Cap with Mesh Filter): Breather Cap with Filter Element – Allows air exchange in the reservoir while preventing contaminants from entering. Top Center (Hexagonal Top Filter): Return Line Filter Element – Used for filtering hydraulic fluid before it returns to the tank, removing fine particles. Top Right (Lever Valve): Manual Directional Control Valve – Used to manually control the direction of hydraulic flow in the system. Middle Center (Small Sight Glass with Bolts): Oil Level Sight Glass – Displays fluid level inside a reservoir or tank. Bottom Left (Black/Brass Component): Pressure Relief Valve – Protects the hydraulic system from overpressure by diverting excess flow when needed. Bottom Center (Threaded Cartridge): Hydraulic Check Valve (or Flow Control Cartridge) – Allows flow in one direction and blocks in the other.