The SramForce Rear Derailleur takes advantage of Exact Actuation, an actuation ratio that delivers precise 3mm shifts in every gear along with the widest range of adjustment available, delivering the best 10 speed performance in the sport. With WiFLi, the rear derailleur lengthens its cage and gets a slight variation in geometry to accommodate an 11-32 cassette. The new range of gears is wider than the standard triple chainring system and saves well over 250 grams.The Sram Force Rear Derailleur is crafted with cutting-edge materials, including a unidirectional carbon-fiber outer mid cage and a magnesium inner link.WiFLi offers a wider gear range and is compatible with cassettes up to 32TExact Actuation means precise, even gear changes throughout the shifting range.Carbon-fiber outer cage and magnesium inner link give strength and light weight..Speeds10.MaterialAluminum B-Knuckle, Magnesium Inner Link, Carbon/Aluminum Cage.Weight190g.Compatibility32T max cassettes.Cage SizesMid cage.