Because it is fast and reproducible, Goldmann applanation tonometry has been the gold standard in tonometry for many decades. It is based on the Goldmann principle – tried and tested during more than 50 years of usage with millions of patients. Furthermore, thanks to the high precision of manufacturing at Haag-Streit, the Goldmann applanation tonometer offers reliable performance over many years without the need for manufacturer maintenance. AT 900 is the original version of the Goldmann tonometer and works 100% mechanically. The digital Goldmann tonometer AT 900 D* adds the advantages of state-of-the-art digital technology. Wireless transfer of the IOP readings and left/right eye position allows direct integration of the AT 900 D* tonometer into an existing patient information system, thus facilitating an ergonomic workflow.