A planar array having plurality of biological recognition molecules including at least two types of biological recognition molecules distributed about a substrate is disclosed. The tensioning system has a lever arm pivotally connected to both the superstructure and the upper end of the marine element and a tension controlling strut member pivotally connected to both the superstructure and the lever arm. The bleed-off mechanism can be opened to enable venting of trapped pressure from the wellbore andor flow path. As the user applies a turning force to the wheel, it wedges against one of the two small rollers, depending on the direction, providing the feeling of resistance to the user as the wheel is turned.