Some relevant details are:

• There is a spring adjuster on the p-pivot.
• There is no cable adjuster.
• It has a single parallelogram spring using ~2.0mm wire.
• The inner parallelogram plate is an aluminium forging (making this a Euclid rather than a Centaur !?).
• The cable is clamped using a hex nut.
• The pulley wheels are plain bearing items in white.
• The inner pulley cage plate is steel and has a spoke deflector.
• There is a strange grey plastic piece covering the heads of the adjustment screws.

• Derailleur brands: Campagnolo
• Categories: Campagnolo - mountain bike madness
• Country: Italy
• Date of introduction: 1988
• Date of this example: unknown
• Model no.: M010
• Weight: 293g
• Maximum cog: 34 teeth (Campagnolo)
• Total capacity: 44 teeth (Campagnolo)
• Pulley centre to centre: 87mm
• Index compatibility: 6 speed or 7 speed
• Chain width: 3/32
• Logic: top normal
• B pivot: sprung
• P pivot: sprung
• Materials: aluminium with a steel inner pulley cage