What number bulb is used in a non-contact tonometer?

In a non-contact tonometer, the specific bulb used is critical for ensuring the device operates correctly and provides accurate measurements of intraocular pressure. The bulb designated as 12419 is specifically designed for non-contact tonometry. This selection reflects the design specifications and functionality required for the instrument, ensuring that it can produce the appropriate air puff needed for measuring the pressure in the eye without making direct contact.

The other options represent different bulbs that serve other purposes or may be used in other types of medical or optical devices, but do not meet the specific requirements for non-contact tonometry. The correct bulb must be capable of functioning within the parameters established for this type of tonometer, which makes option 12419 the appropriate choice.