An agricultural baler has a plunger for compressing harvested material to a bale in a chamber, a crank mechanism connected to the plunger for the purpose of driving the plunger, wherein the crank mechanism comprises at least one first crank and at least one second crank, a drive mechanism for driving the first crank and the second crank, wherein the drive mechanism is configured such that, when the first and second crank are driven, the first crank and the second crank rotate in opposite directions.
