The fully electronic braking system eliminates a physical connection between the brake lever and the calipers. Nevertheless, ...
I’ll let pictures do as much of the talking as possible. Shimano 105 Di2 Hydraulic Disc Brake Dual Control Levers (2×12-speed) – Left (front derailleur/brake) and Right (rear derailleur/brake) ...
Tektro was something of a budget brand. Mostly appearing on cheap bikes, it  didn’t quite have the brand image to sell ...