The Compass 4D™ MIS Retractor system is designed to aid in exposure. retraction, decompression, and disc preparation of the spine. Compatible with all products used in Aurora's Screwless Procedure, the Compass 4D provides optimal access while minimizing tissue damage. Crafted out of titanium, the Compass 4D features three independently moving blades, with an optional fourth blade. Blades are available in various lengths to accommodate patient anatomy and approach. Multiple lights are available to increase the visualization during procedures; one to illuminate the approach, and a disposable, sterile-packed light to illuminate the target area. A disposable, sterile-packed optional probe is also available to use with the neuromonitoring system of choice.