To produce the ideal bale, density is controlled by two strong springs. After the core is formed and the bale starts to grow, two electronic monitoring devices - mounted between the tailgate and the baler frame - monitor pressure in the bale chamber. The required density level is pre-set on the performance monitor and when this preset level is reached the wrapping process will automatically start after giving the operator a warning signal. This simple and efficient control system allows the operator to make precise density adjustments to suit the crop conditions.