Mongoose Argus TRX Fat Tire Mountain Bike for Adults, 26-Inch Wheels, 16 Speeds, Red The world of fat bike adventures is waiting... get in on the fun with the Argus fat tire mountain bike by Mongoose. This fat bike comes with a Mongoose MTB aluminum fat tire hardtail frame and alloy fork with 135 mm spacing for a strong, stable ride. An 16-speed trigger shifters offer ideal gearing for varied terrain without overwhelming younger riders. There are mechanical disc brakes to supply quick, effective braking even in slippery weather on bumpy trails. But let's be real, the tires are the star of the show. Knobby, oversized 4-inch wide fat mountain tires provide tons of traction, quicker stopping power and extra stability on tough trails. You don't need anyone to tell you how awesome they look. Finally, the Mongoose MTB saddle is comfortable, offering added support for long arduous rides. From rocky singletrack to snowy hills, the Mongoose Argus is built to handle it all.