Lego Batman Set of 4 Helmet, Mask, Cowl: Black, Dark Blue, White, Silver | eBay
If there where to be Flash movie Sets in the future, do you think LEGO would re-use this Batman Cowl piece that is only accessible in two UCS sets? (BrickLink - 51008pb01) :
LEGO 76182 Batman Cowl revealed! - Jay's Brick Blog