How do I get to the inlet filter on a single knob unit this is for a moden unit

How do I get to the inlet filter on a single knob unit this is for a moden unit
You will have to repost your question so we can understand it. If you're referring to a one handled valve we need to know, 1) what type of valve it is, Tub, shower, tub/shower lavatory or kitchen, 2) the brand name of the valve, 3) describe "inlet filter", could you be meaning the cartridge? Back to you, Tom