This style peaked in 1969, when Mustangs like the Boss and Mach 1 received rear window louvers as a factory-installed option called "Sports Slats," quickly copied by 1970s Mopar E-bodies like the ...

Window louvers are those horizontal slats you see a lot in some cars from the 1980s and prior, along with more recent muscle cars like certain Mustangs and Camaros.

I’m sure some people reading this are old enough to remember when window louvers were prime automotive fashion accessories. The somewhat ominous-looking sun-deflecting slats were all the rage on ...

SilverHorse Racing offers an exclusive line of window louvers for ’05-present Mustangs. Pictured here is its Flush-Mount Quarter-Vent Louver kit for ’10-current Mustangs (PN S297-300, $354.99).

Reddit user carnvalOFoz posted a proof of concept for rear window louvers on the 2017 Mazda MX-5 Miata RF. They don’t look bad, especially for a Photoshop job.

Update: The louvers have now landed in the real world and the artist is showcasing the final version on his red RX-7, as well as on another build of the sort, via the second Insta post below.