A new 1.1 Tesla Lambertson for Main Injector injection/extraction and Tevatron injection has been designed and the magnetic properties of the first production magnet have been measured. The Main Injector Lambertsons will be used for injection of 8.9 GeV/c antiprotons from the Antiproton Source and 150 GeV/c antiprotons recycled from the Tevatron, and the extraction of 120 GeV/c protons for antiproton production, 150 GeV/c protons for Tevatron Injection, 120 GeV/c resonant extraction, and the Main Injector abort. This magnet must accommodate Main Injector and Tevatron circulating beam in its field free region while the field region is at all excitation levels with minimal impact on the circulating beam. The design specifications and results of magnetic measurements in both the field region and field free region for the first production magnet are discussed.