Is an air filter provided in asi or turn and bank indicator in aviation instruments?

A turn and bank indicator is electric and does not require vacuum. as far as an ASI? Is the acronym correct?

Answer

The ASI (airspeed indicator) has a pitot tube input and static air input. It measures the difference in pressure between the two and air does not flow through the instrument, so no air filter would be required.

The vacuum pump driven by the engine, works the AI, (artificial horizon) and directional gyro. There is a small filter under the instrument panel, replaced annually i think.