1.Lightweight aluminum frame: Weight is the fundamental aspect and arguably the most important spec for a bike. Featuring a lightweight aluminum frame design, the F=MA is the ultimate mountain bike for every cyclist.Please do not hesitate to contact us if you have any queries about the bike (1-888-881-BIKE). We proudly stand behind our bike with a limited lifetime warranty. 2.SHIMANO DERAILLEUR - The indexed Shimano TZ-500 derailleur and shifter can deliver 21 speeds of precise and smooth gear shifting on-demand for any need of power and torque for the rider. 3.DUAL DISC BRAKES - The dual disc brakes design ensures consistent stopping power in any terrain and weather condition—an ideal combination for a high-performance mountain bike. 4.SUSPENSION - The suspension fork absorbs bumps in the trail or roads and keeps the front wheel stick on the ground to improve outstanding comfort and handling.Recommend for a rider height of 47”~63” (120~160cm). 5.EASY TO ASSEMBLE - The F=MA is 85% pre-assembled and easy to put together.Follow the instructions carefully before assembling this well-equipped aluminum mountain bike.Please pay attention to the installation direction of the handlebar and fork.