Système de cage à bras unique SIGEYI "SACS"

The SACS is SIGEYI's answer to oversized pulley cages[split]

SACS stands for Single Arm Cage System. 

Specifications
Model: SACS-SHR
Pulley: 12T Upper, 16T Lower
Compatible with Shimano R8000/R8050/R9100/R9150 rear derailleur
Cassette: Up to 11-34 range
Warranty: 2 Years

Mfr Claimed Weight
49g