Donner Yellow Fall Vintage Pure Analog Delay Guitar Effect Pedal True Bypass Pure analog Whole circuit delay, clear, plump and smooth New Delay effect. Aluminium-alloy classic, stable and strong Aluminium-alloy classic, stable and strong. True bypass provide transparent tone,LED indicator shows the working state. 3 Knobs, ECHO is mix, TIME for 20-620ms delays, FEEDBACK is the repetions. Important instructions 1-Please make sure the the diameter for power plug using is 5.5, and the power for the adapter is OUT-DC 9V- 500mA 4.5W. The misusage for power adapter usually can lead to a loud buzzing sound Package includes: Donner Yellow Fall Delay Pedal and Owner Manual, Power supply(not included) MaterialAluminum-alloy classic. Time of Delay: 20ms ~ 620ms. Input Impedance: 1 M Ohms. Output Impedance: 490 Ohms. Working Current: 42 mA. Power Supply: 9V DC adapter (Negative in the center). Dimensions: 95mm (D)*44mm (W)*48mm (H). Weight: 240g (with box). Power Supply9V DC (Negative in the center). Echo KnobEcho to adjust the delay of the level. F. back KnobF. back to adjust the delay of the feedback. Time KnobControls delay time for 25ms-600ms. Input &amp; Output JackAnalogy though 1/4 mono audio jack. LED LightLED indicator shows the working state. Full metal shellAluminum-alloy classic, stable and strong. True BypassTrue bypass for zero tone coloration. Supply Voltage: 4.5V-5.5V. CD2399GP-SOP-16GAIN=29dB. Adjustable treble=10dB(8kHz). Bass adjustable=10dB(100Hz). Delay times=113.7-228ms Speed Steples. Rate=20Hz (-3dB), Delay noise=30Hz-8kHz(-3dB). Low noise No&lt;-90dBv Typical. Low DistTHD&lt;0.5%Typical. Auto Rep air reset function. The external resistor adjustment VCO.