Medium-position overflow function, the oil will flow back to the fuel tank when not in action. There will be no internal leakage or external leakage under no-load and load conditions. 1Pc x 2CH/3CH/4CH/7CH Hydraulic Oil Valve Controller With Servo. Item color displayed in photos may be showing slightly different on your computer monitor since monitors are not calibrated same.The item "RC Excavator Bulldozer Hydraulic Oil Valve Controller With Servo" is in sale since Sunday, July 11, 2021. This item is in the category "Toys & Hobbies\Radio Control & Control Line\RC Model Vehicle Parts & Accs\Other RC Parts & Accs". The seller is "79ryan7" and is located in ShenZhen. This item can be shipped to North, South, or Latin America, all countries in Europe, all countries in continental Asia, Australia.