Brake levers are the mechanism that is located on the handlebar at the front of the bike. There are generally two located on either side of the handlebar for both hands and their function is to control the brake pads that are positioned next to the wheels of the bike. All brake levers are different depending on the brand and type of the bike, but they all are activated by a tight squeeze of you hand which will make the brake pads tighten against the wheels to slow down the bike. Brake levers come in a range of different colours and come attached to a new bike when purchased. They can be sold individually but be cautious as not every brake lever will suit every bike.