The Zone60 HG is a semi-automatic laser rotator. Semi-automatic means that the laser self-levels only when in Level mode, not when grade is entered. The Zone60 HG is a laser tool for general construction and leveling applications such as: Setting forms Checking grades Controlling depths for excavations If set up within the self-leveling range, the Zone60 HG automatically levels to create an accurate horizontal plane of laser light. Once the Zone60 HG has levelled, the head will start rotating and the Zone60 HG is ready for use. 30 seconds after the Zone60 HG has completed the levelling, the Elevation Alert (H.I.) function becomes active and protects the Zone60 HG against changes in elevation caused by movement of the tripod to ensure accurate work. The Zone60 HG can also be used to create sloped planes for applications such as: Driveways Parking lots Landscaping In Grade mode the Zone60 HG checks first the position of the beam at level, then adjusts to the desired grade input. If a single grade is entered, the cross axis will continue to self-level. Once the Zone60 HG has reached the desired grade, it does not self-level, but is monitored by Bump Alert and temperature change functions to ensure reliable grade values.