Gears are precision machined by Digga from high grade quality alloy steel, providing you with a highly efficient pressurized gearbox which ensures no leaks and minimal maintenance. Built in pressure relief valve (PRV) ensures max volumetric effeciency for consistent & efficient pile installation throughout the working day. Integrated Energy Control Valve. This revolutionary bypass valve is fitted to the drive to control the rapid decompression of oil. Engineered hood and ears for maximum strength. Specifically designed for heavy duty drilling applications. The Digga 2 piece shaft, is a separate component to the planetary carrier, isolating the planetary gears from the pushing, pulling & bending forces generated by the machine.