The SRAM Red XPLR AXS E1 is SRAM's top-tier 1x13-speed wireless gravel groupset, built around the hangerless Full Mount rear derailleur and a 10-46T cassette. It is designed for gravel racing and fast off-road riding, and fits frames with a UDH (Universal Derailleur Hanger) dropout only. Key Features 13-speed, 10-46T cassette with a 460% gear range and tight steps in the higher gears Full Mount rear derailleur bolts directly to the rear axle via the UDH interface no hanger to bend or align No limit screws or B-tension adjustment derailleur setup is fixed by the mount Strongest clutch SRAM has fitted to a gravel derailleur for secure chain retention on rough ground Replaceable derailleur cage, pulleys, outer links and mount for trailside or workshop repair Red E1 shift/brake levers with a reshaped hood to suit a wider range of hand sizes SRAM claims 80% less lever effort braking from the hoods and 33% less from the drops versus the previous Red Wireless AXS shifting, customisable through the SRAM AXS app Hollow carbon Red crank arms on a DUB Wide spindle with a direct mount X-Sync chainring Runs on the 12/13-speed Red E1 Flattop chain with PowerLock connector Compatibility Frame: UDH dropout required the derailleur will not fit a conventional derailleur hanger Chainstay length: 415 mm minimum with the supplied XPLR (Wide) crankset and 47.5 mm chainline Rear suspension frames where chainstay length changes through the travel are not supported Freehub: SRAM XDR driver body required Brakes: flat mount callipers for flat mount frame and fork Rotors: Centre Lock hubs required for the optional Paceline X rotors Bottom bracket: SRAM DUB Wide bottom bracket to suit the frame's shell standard Chain: SRAM Flattop chains only Included SRAM Red AXS E1 shift/hydraulic disc brake lever and calliper left/front, 950 mm hose SRAM Red AXS E1 shift/hydraulic disc brake lever and calliper right/rear, 1800 mm hose SRAM Red 1x E1 XPLR DUB Wide Direct Mount crankset SRAM Red 1x XPLR AXS E1 13-speed rear derailleur, 46T max SRAM XG-1391 XPLR E1 13-speed cassette, 10-46T SRAM Red E1 Flattop chain with PowerLock SRAM eTap AXS battery Optional Extras (Additional Cost) SRAM Paceline X Centre Lock rounded rotor front SRAM Paceline X Centre Lock rounded rotor rear SRAM AXS battery charger Required Separately SRAM DUB Wide bottom bracket Disc rotors and battery charger, if not selected as options above UDH-equipped frame with flat mount brake mounts Rear wheel with SRAM XDR driver body Specifications Specification Detail Drivetrain 1x13-speed, wireless electronic (AXS) Discipline Gravel Rear Derailleur Mount Full Mount (UDH frames only) Max Sprocket 46T Cassette XG-1391 XPLR E1, 10-46T (10/11/12/13/15/17/19/21/24/28/32/38/46) Gear Range 460% Freehub Standard SRAM XDR Crankset Red 1x E1 XPLR, hollow carbon arms, direct mount chainring Spindle DUB Wide Crank Length 165 / 170 / 172.5 / 175 mm Chainring X-Sync direct mount, 40T Chainline 47.5 mm Q-Factor 150 mm Chain Red E1 Flattop, 12/13-speed, PowerLock connector Brakes Hydraulic disc, flat mount callipers Hose Lengths 950 mm (left/front), 1800 mm (right/rear) Rotors (optional) Paceline X, Centre Lock, rounded edge Frame Requirement UDH dropout, 415 mm minimum chainstay SRAM's best gravel drivetrain wireless, hangerless and built to take a beating.