Brompton Front Derailleur / Bracket.
 

I got one of these from C M Wasson, it's custom made for the purpose,

Did the ratio calculations, then went with a Bigger low gear range Drop,

thru getting a Schlumpf Mountain drive crank instead .

So It's un used , can return for credit to the charge card account, or I thought I'd mention

it and see who else may like a bit wider gearing range on their Brommy.

Clamps to frame, adds a braze on mount for that sort of derailleur , Got the F derailleur,

and a thumb shifter to sell .

Drop a PM and we can converse..