Omega D-3 and D-4 enlargers are 4x5 autofocus enlargers which require an autofocus track for each focal length lens used. This is the autofocus track for 150mm lenses, typically used for enlarging 4"x5" format negatives. Installation and adjustment instructions, as well as an adjustment wrench, are included. The tracks are used, so there will be minor cosmetic marking, but they are in perfect working condition.
Note: For proper operation of the D-3 and D-4 autofocus systems, 150mm lenses must be mounted on a 5¼" high lens mount. Ensure that your lens is mounted on the correct lens mount.