Ambrielle bras are from JC Penney’s stores. This style may be on the way out; this one was recently purchased in a store at a sale price and is available online in limited quantities. It does come in several different colors. The bra is very lightweight; the underwired cups are seamless with very light padding and are made of a breathable material to keep you cool in hot weather. Straps are elasticized in back and have metal adjusters. Here is a video from Penneys about it.
I tried dying the bra blue using Rit dye in Evening Blue and here are the results. As expected different materials take the dye differently, but I think the result looks pretty good. Polyester does not take this type of dye well so the cups, which are a polyester blend, came out lighter than most of the other parts, which are probably nylon. Most of the stitching shows up white indicating that polyester thread was likely used.