The single nip calenders consists of factors such as front load, back load and deflection which controls the caliper paper of the sheet. Zone profiling is also used to adjust the caliper profile of the sheet. The hard nip calenders are well suited for final calendering of different types of newsprint, board and fine papers. Pre calendering of coated paper and board is also another area of application. The dry calendering or hard nip calendering can be done with two or more rolls or one or more nips. Soft calendering can be applied to both new production lines as well as rebuilds. All levels of the required accuracy of profile control are achieved without the limitation of paper width and machine speed. Wet stack or multi-nip calendering is typically done with three or more rolls and two or more nips. In wet stack, water is added to the sheet surface in between one or more nips using water boxes. The added moisture and applied nip pressure develop uniform nip pressure profile and good smoothness of sheet.