Shimano 600 Tri Color RD-6401 Short Cage Rear Derailleur - Gringineer Cycles
NOS Vintage Shimano 600 Ultegra Pulley Bolt for RD-6401 Rear Changer | Bicycle Parts and Accessories | Gumtree Australia Geelong City - Geelong West | 1240639621
Shimano 600 Rear Derailleur RD-6401 - Two Bikes
Vintage Shimano 600 Ultegra Rear Derailleur Tri Color RD-6401 6400 Index 8s | eBay
Vintage Shimano 600 Ultegra Rear Derailleur RD-6401 Tri Color Short Cage Bolt On | eBay