Convert SRAM 11 speed to 12 with new e*thirteen TRS Plus upgrade kit | off-road.cc
Ratio's New 1×12 Road Upgrade Kit Converts 10 or 11 Speed to 12 Speed | The Radavist | A group of individuals who share a love of cycling and the outdoors.
1x12 Road Upgrade Kit - Ratio Technology
Ratio 2x12 DIY Kit takes 11sp SRAM mechanical road to 12sp - Bikerumor