About SRAM Apex XPLR D1 12 Speed Rear Derailleur
You want your bike to do everything, so you need gears that can do everything. The Apex XPLR derailleur hits the sweet spot of smooth jumps over a big gear range, all with unmatched chain security and the simplicity of a 1x drivetrain. Quietly and quickly shift across our 12-speed cassettes with 44T large cogs, knowing you’ll have the gears 
you need.

Features
Compatible with cassettes with 
44T large cogs

Use with Flattop chain

Works with 12-speed mechanical 
Apex and Eagle shifters

Clutch controls chain tension for consistent shifting

X-HORIZON straight parallelogram design limits all movement to the horizontal axis, which makes ghost shifting impossible while also reducing shift force

Cage Lock technology makes for fast wheel changes or chain installation

Technology
Cage Lock: With CAGE LOCK technology in the rear derailleur, wheel removal and installation—as well as chain installation—becomes faster and simpler. Just push the cage forward to create slack and lock it into place.

X-Horizon: This rear derailleur’s “straight parallelogram” design limits all movement to the horizontal axis, which makes ghost shifting impossible while also reducing shift force. For quicker, more exact shifting, the large upper pulley offset design maintains a constant chain gap across all gears.

X-SYNC: SRAM X-SYNC 1x chainrings provide the highest level of performance and durability. The SRAM X-SYNC tall square teeth edges engage the chain earlier than traditional triangle shaped teeth. The sharp and narrow tooth profile, as well as rounded chamfer edges, help manage a deflected chain. To provide the best possible performance in muddy conditions, the X-SYNC chainrings have been designed with mud-clearing recesses for the inner chain links and rollers. Engineered in Germany, X-SYNC rings are an integral part of the SRAM 1x drivetrain. Accept no imitation.

Specifications
Speed (RD): 12s

Cable Pull Ratio: X-actuation

Cage (RD): n/a

Max Tooth: 44

Colour (RD): Black

Pulley Bearings Material: Steel

Cage Material (RD): Aluminum

Model ID: RD-APX-1-D1

About SRAM
Founded in 1987, SRAM (an acronym of the 3 founders names, Scott, Ray and Sam) is a privately owned bicycle component manufacturer located in Chicago. They're known for developing many of the inovative technologies used in bikes today including ETAP wireless electric shifting, Grip Shift, dedicated single chain ring drivetrains, narrow wide chainrings and more. Sram also own bicycle component brands Rockshox, Quarq, Zipp and Truvativ.