Box 3 Prime 9 X-Wide Group Set

From 11 to 50t in 9 speeds! It's a lot of range. It's rare. And it's pretty good value.
 
Wide range 9 speed multi-shift group with up to 3 gears per shift
Simple durable performance without all the bells and whistles
Set includes 11-50t cassette, rear derailleur, shifter and chain
Wide ratio with consistent progression (11-13-15-18-22-28-34-42-50t)
Shifter offers 2pc pull lever with up to 3 gears per shift
Glass fiber / nylon composite, steel and aluminum construction
Matte black finish