This is a envelope filter /state variable filter effect with several features.
The OLED screen will show the actual characteristics of the filter in a familiar way.
'Sense': Adjust the sensitivity
'Res': Adjust the resonance
'Freq': Sets the corner freq of the actual filter
'24/12':Adjust the gain of the output.

In modulation mode it adjust the mod freq. 
'Filter': Change the state ofthe filter; Lowpass, bandpass or highpass
'Direction': Set the direction the filter moves when you play. Mid pos is fixed.
You can connect an expression pedal to both EXP and CV.
Pedal connected to CV will adjust the modulation speed when Modulation mode is activated.
Expression pedal connected to EXP will adjust the corner frequency of the filters.

To activate the modulation mode, hold the rigth footswitch for 1 sek. Then the LED will blink in the tempo of the modulation. Now you can tap the tempo or adjust it with the 24/12 knob. You can also connect an exp.pedal to CV adjust it. 
SPECS:
Power: 9V negative center 220mA; Separate, isolated power.
Max input level: 2.8Vp-p
Input imp: 500kOhm
Out imp: 1kOhm