Wide pivot link design suppresses flex for more precise shifts. Will work on 9sp systems when used with a 10sp chain. Braze-on fits frames with pre existing front derailleur braze-on (can also be used with 31.8mm or 34.9mm braze-on/band-clamp adapters), or use pre-sized band-clamp versions: 74g (braze-on double) / 106g (braze-on triple).