The Sac Plat, French for "flat bag", was introduced by Louis Vuitton in 1968 and designed to look like a shopping bag. Sotheby's explains that, like the Keepall, it was meant to be folded into luggage and used on arrival at a travel destination.
In recent years Louis Vuitton has leaned into the fashion for miniature versions of its classics. The Petit Sac Plat, released in 2020, has become highly sought after; it can be carried by its handles or worn across the body with a strap.
The Sac Plat has also been used for special editions. One example in Sotheby's guide is a version in Takashi Murakami's Cerises print, with his smiling cherries scattered over the Monogram canvas.