The Fender Classic Re-Issue Phaser pedal.

“Shift” into high gear with the Fender Phaser, great for both guitar and bass and really super-whoooshy-sounding! Stylishly retro ’70s-era good looks, sure, of course—but you also get efficiently versatile intensity, rate, bypass and frequency controls that let you tailor that ethereal phasing sound to utter perfection. You can easily emphasize treble or bass frequencies, and the big “rate” dial glows blue and red in synch with the phase shift rate, which is really cool and scientific-looking and stuff.  Also included is a very cool Fender embroidered velvet carrying bag. 

Features:
• Rate—This knob controls the rate at which the phase shifting occurs. The rate control knob alternately illuminates blue and red at the same rate as the phase shifting.
• Intensity—This knob adjusts the intensity of the Phasing effect.
• Frequency—This knob adjusts what frequencies are affected by the phasing action. Fully counter-clockwise causes the bass frequencies to be affected most by the phasing action, fully clockwise causes the treble frequencies to be most affected by the phasing action.
• Bypass Switch—A “true-bypass” of the phaser effect. Turns the phasing effect on-off.
• Output Jack—Connect to the input of your amplifier (or other audio device).
• Input jack—Plug your guitar (or other audio source) in here. Un-plug the input plug from this jack to turn off the device and save power (very important) when not in use.
• DC Input Jack—Plug in a AC- 9V DC adaptor (see specifications) into this jack to eliminate the need for batteries.

Specs:
• Input Impedance: 470kOhm
• Nominal Input Level: –20dBV
• Output Impedance: 4.7kOhm
• Nominal Output Level: –20dBV
• Recommended Load Impedance: 50kOhm or Greater
• Power Requirements: 9VDC (Center Pin = Negative); 40mA Minimum