J Lo and A-Rod's Met Gala Balmain Outfits Up for Auction

J Lo and A-Rod's one-of-a-kind matching Met Gala outfits are going from the red (and white) carpet to an auction to raise money for (RED)'s fight to end AIDS.

The couple slayed Monday night in custom-designed Balmain looks from the creative director ,Olivier Rousteing. The theme was "Heavenly Bodies: Fashion and the Catholic Imagination," hence the cross on J Lo's chest.

Her dress took over a month to make ... the jewels on the feathers were sewn on by hand, which explains the $5k starting bid. A-Rod's tux starts at $1,500.

The auction is a cool concept ... if you can rationalize spending that much on clothes, and also considering there's zero chance they would re-wear this stuff. Rousteing's other designs from the night for 'Daily Show' host Trevor Noah, Juliette Binoche and more are also up for auction.