Hydraulic Directional Valve 8mpA with 4mm Connector for 1/12 1/14 1/16 RC Toys. The valve block supports self-upgrade for additional channels. Please refer to the tutorial video above; the entire upgrade process is very simple and easy to operate. Use pressure within 8MPa. Processing technology: CNC super-finishing. Product medium: 46# hydraulic oil. Product features: Supports future upgrade for more channels, delicate operation, small size, beautiful appearance, etc. Note: Without central oil return function, you can use it with the overflow valve from our store. When the cylinder reaches the longest and shortest stroke, the overflow valve automatically opens the pressure relief valve to drain the oil into the tank. Fast Responses: We reply to all customer inquiries within 24 hours, ensuring your questions are answered promptly. We’re here to help with any concerns or issues you may have.