7075 Aero Spec Aluminum with T6 heat treatment, lightwight yet ultra strong and durable
Black, Silver, Golden and Titanium Colours
Stock Brompton crankset compatible (BCD130) for most economic upgrade.
60T is about the biggest size for Brompton Chainring with perfect fold. You might need narrower front axle hook (depending on Brompton frame production tolerance). Please refer picture below.