This is a used Shimano Dura-Ace RD-7970 Di2 10-speed rear derailleur. The pulley cage stopper pin has been replaced with an aluminum bolt instead of the original part (see photos), but this does not affect functionality.
SHIMANO Rear Derailleur 9v SS-RD-R3000 Sora
SHIMANO Rear Derailleur MTB DEORE M5100 1x11V Long Cage 51
Falcon Vienne Womens' Mountain Bike Black/Teal, 17" inch steel frame, 18-speed Shimano rear derailleur and micro-shift rotational shifters strong and lightweight deep-section alloy wheel rims
SHIMANO Rear Derailleur MTB DEORE XT M8100 1x12V 45 Teeth Black
Shimano Rear Derailleur Cable Fixing Bolt & Plate - RX812 - Y3GF98020
Shimano Rear Derailleur Cable Fixing Bolt & Plate for Saint, XT, SLX - Y5W798030
