These are one of the best chorus pedals on the market I reckon. Maxon are so badass that they just made their own analog bucket brigade style chips to power this blue beauty. It does subtle tasty analog chorus, covering all that CE-2 style ground, or you can dime the knobs and the little wet/dry mix on the top and get absolutely munted to wobbly oblivion. 

Model: Maxon CS-550 Stereo Chorus Pedal
Made: Japan, 1998 (serial 981HN087)
Type: chorus, analog
Power: 9v DC negative supply (not included)
Switching: true bypass
Mods: third knob replaced with mismatched knob (not pictured)
Accessories: none
Condition notes: used, few minor marks marks, fully functional. Overall good condition