2013 Shimano Zee Shadow Plus Rear Derailleur 3

The Zee RD-M640 features Shadow Plus technology proven to reduce chain slap, drop and impact noise and the 10-speed short cage RD’s low profile tucks safely below the cassette cogs. With two spec options that enable a typical MTB cassette (11-32,11-34,11-36) or a close ratio road cassette (11-23,11-25,11-28), Zee is ready to handle the needs of enduro and DH racers. 10-speed also offers complete compatibility with Dyna-Sys MTB product and Shimano’s latest chain and cassette technology.