Bull´s eye levels GN 2280 are used to check the horizontal position of jigs, machines, devices, appliances and instruments.The mounting threads offset by 120° allow the spirit levels to be aligned in relation to the mounting surface. An alignment ball at the bottom surface of the adjustment plate serves as tilting point. Specific tightening torques of the bolts allow to be achieved, so that the bubble is located inside the marking ring once the horizontal alignment is reached.