CESSNA GYROSCOPIC RATE OF TURN INDICATOR CESSNA P/N C661003-0201 S/N: 607578. MFG Part No. 1683 Mfd bg Brittain Industries, Inc Glass is clear and the markings are very legible. The ball moves freely has some signs of visible wear and a small dent in the back. See picture. Unit is stamped Oct. 18, 1997 with warranty expiring Oct 15, 1997. Warranty sticker is still intact on the unit. Unit is sold untested, as is, with no guarantees Thanks for offerding and remember to keep your nose up in the turns!