Used 2020 Massey Ferguson 1840 MF 1840 Baler Serial # KHBS3110 The system automatically regulates pressure on the pressure rails of the OptiForm bale chamber to ensure consistent bale density as conditions vary across the field and throughout the day. A small hydraulic reservoir, pump and pressure regulator at the front of the baler, control the oil pressure in the density control rams. The MF 1840 carries 10 balls of twine which is enough for the longest days work. The large dimension of each compartment allow ‘super large’ size twine spools to be used, enabling even more twine to be carried.