Aluminum alloy CNC machined lightweight tensioner arms, derailleur, fixture, and thumb shifter.
Compatible with P/T Line or Electric P Line frame (A/C Line version is in other listings). Comes with X7 advanced Cog Set on stock wheelset for 7-speed 11-28T (#X7AdvancedCogSet).
The largest cog is 28T (vs. the original max 18T on P/T Line).
This modification is more difficult than the rather easy "plug and play" X3 Unibody Cogset external 3-speed upgrade. (please expect some more time and patience to finetune the result).
Do not recommend this as a DIY project, please consult your LBS mechanic before ordering.