Brakes can either be mechanical or hydraulic.
Mechanical brakes use a metal cable to connect the brake levers to your brake pads. Mechanical brakes are compatible with both our INLINE and HYDRAULIC brake sensors. Note the grey, metal cable on the right of this photo:
Hydraulic brakes use tubing filled with fluid to connect the brake levers to your brake pads. Hydraulic brakes are compatible with our HYDRAULIC brake sensors, but not compatible with our INLINE brake sensors. Note the larger tubing, and the lack of any metal cable in this photo:
One other thing: Most brakes on front wheels are rim brakes. Disc brakes are common too, and sometimes bikes are fitted with hub brakes. Rim Brakes and Disc brakes are fully compatible with the Swytch kit. Sadly, hub brakes are not currently compatible.
Rim brakes are located at the top of your wheel. They look like this:
Disc Brakes are located on either side of your wheel axle. They look like this:
Hub Brakes are located inside the centre of your wheel. They look like this: