My close friend (trans guy) is moving away and I want to get him a gift. His chest is not super easy to bind (I would say 32DDs at least) and he's been pretty open about having difficulties finding binders that fit, without resorting to any unhealthy methods. I want to get him a gift certificate for a website where he can buy a good binder specifically for large chests but I don't use binders so I don't really know which ones would be better. Does anyone have any recommendations?

(I would prefer not to just ask him his cup size specifically because I would like the gift certificate to be a surprise... but I guess the surprise isn't totally necessary!)

Thanks!