The present disclosure provides a device and method for measuring or distracting an intervertebral distance of an intervertebral space between a first vertebral body and a second vertebral body. The device includes a displacement unit having first and second engagement members. Displacement of the engagement members is caused by actuating an actuator on the device. In response to actuation, a force transfer carrier drives the displacement between the engagement members. The force transfer carrier is connected to the engagement members by a plurality of linkages. The distance between the engagement members is indicated by a gauge having an indicator rotatable about a pivot point. The distance between the engagement members varies in a nonlinear relationship to the movement of the force transfer carrier
