This is the Mercury Cougar Eliminator, as built in 1970. The Eliminator was a special package for the Cougar which included a number of stripes across the car much like the Mustang BOSS. The basic engine was the 351ci Windsor engine but a number have been fitted with 428ci and BOSS 302 engines.
Company press release, last updated before 12 / 01 / 2004
"I am a hardcore GM fan, but the ONE and only non-GM car I've owned kind of fell into my lap a few years ago: a 1987 Cougar XR7 with the 5.0 liter V8. Ever since then I've had a small place in my GM stamped heart for nice Cougars. The first generation cars are beautiful, and I'll probably buy one eventually and drop a Chevy LS1 into it. Just like ""American Graffity"": Ford body with GM smallblock power! One interesting fact about the Cougar is that it influenced the Camaro... Originaly the Camaro was to be named the ""Panther"" and if you look at the first generation cars you can see some cat-like cues. The rear quarters look a lot like a cat's rear shoulderblades when it's crouthed down ready to pounce. A '67/'68 Camaro is very cat-like, especially from the side. Anyway, the point of this story is that at last minute in early 1966 GM discovered that Mercury was getting a Mustang clone and calling it the Cougar and so it was decided to just go with a different name, one beggining with a ""C"" as was the tradition at Chevy then."