Aren't they for set frequencies ? Out = 250Hz , In = 800Hz.
Since you've no switch the instructions below give a list of caps you can use instead.
https://bartolini.net/wp-content/uploads/Docs/NTMB_Wiring.pdf
But what you are saying though is there is two preset freq's with boost and cut depending on whether the switch is in or out, and that makes perfect sense.