The 5 knobs are:
Rate： modulation speed adjustment.
Depth：modulation depth adjustment.
Fdbk: Feedback coefficient adjustment(The middle position is 0,and the two sides are respectively positive and negative feedback)

Selection knob for Flanger effects :
1:mixing ratio for Digital flanger effect.
2:mixing ratio for Analog Flanger effect.
3:mixing ratio for Thru Zero Flanger effect.

Selection knob for modulation waveforms:
Sine:sine wave.
Tri1:triangle wave 1.
Tri2:triangle wave 2.
Sawup:Upper sawtooth wave .
Sawdown:Lower sawtooth wave .
Trapezoid:trapezium wave.

**Be sure to use DC 9 volts for power supply.

Electronic parameters:
Working voltage: DC9V
Working current: 50mA
Case material: aluminum alloy
Item weight(g): 285
Item size(mm): 120x65x50
Packing weight(g): 400
Packing size(mm): 145x90x60