Shifters
Shimano Shimano GRX ST-RX400-L Left Shift / Brake Lever
Left · hydraulic brake / front shift
Requires companion components
Independently sold control requires its compatible opposite-side control and brake system.
Compatibility: reviewed
Known specifications can be used by the compatibility engine.
Retailer offers
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Catalog trust
Evidence and freshness
Technical-source dates and retailer offer checks are separate. A retailer check does not validate compatibility.
Report a correction- Technical review
- Aug 6, 2026
- Compatibility review
- Reviewed Aug 6, 2026
Approved technical sources
- Shimano 2026 GRX component ordering catalogManufacturerSource checked Aug 6, 2026Evidence reviewed Aug 6, 2026
Technical data
Specifications
- Speeds
- 10-speed
- Supported speeds
- 10-speed
- Compatible drivetrain families
- Shimano GRX mechanical 10-speed
- Front speeds
- 2x
- Shift actuation
- Mechanical
- Control style
- Drop Bar Integrated
- Brake control interface
- Hydraulic Mineral Oil
- Control clamp diameter
- 23.8 mm
- Included control sides
- Left
- Left control functions
- Brake, Front Shift