Fit Link - Braze On Front Derailleur Adapter - Junior's Solution
Shimano SM-AD91 Clamp for Dura-Ace/Ultegra/105/GRX Braze-on Front Derailleur - bike-components
M Part Cycling M:part 28.6 - , 28.6mm M Part Front Derailleur Clamp For A Braze On Front Mech 28 6 Black 6mm, Black, 3 size UK : Amazon.co.uk: Sports & Outdoors
FOURIERS Alloy Road Front Derailleur Clamp Adapter 31.8mm 34.9mm FD Clamp Braze on Direct Mount for XO X9 X7 Road Bike Bike|Bicycle Derailleur| - AliExpress