Rectangular baler comprising a bale chamber (201) adapted to contain one or more bales a compacting plunger (203) for advancing crop material in a direction (F) towards a discharge opening of the bale chamber wherein the rectangular baler further comprises at least one friction block (208) mounted moveably in a wall (202) of the bale chamber such that at least a part of each friction block is moveable out of the wall and biasing means (209) adapted for biasing said at least one friction block in a position wherein said at least one friction block protrudes out of the wall.
