Shimano GRX ST-RX820-LA Brake/Seatpost Remote Lever - Left For Hydraulic Disc Brake Lever with Dropper Post Remote. The Shimano GRX ST-RX820 left dual control lever delivers light and responsive mechanical shifting for mixed-terrain riding and racing (Note: LD0374 is a non-shift dropper post remote variation for 1x set ups). The ergonomic shifter design improves comfort by decreasing pressure on your palms while the textured anti-slip brake lever surface increases control on bumpy terrain. The SERVO WAVE brake lever action provides greater braking power with improved control.