Front derailleurs for mountain bikes are designed to slough off the grit, dirt, mud and water to give you a smooth and quick shift. The front derailleur, being so close to the crank assembly will get a lot of splashback, being able to handle the debris from the trail and still give you consistent shifting is the hallmark of a good mountain bike derailleur. Check out our selection of SRAM & Shimano derailleurs, made from high tech materials and top notch engineering.