McLaren have launched the MP4-27, which will lead the challenge against World Champions Red Bull in the coming season.
Lewis Hamilton and Jenson Button unveiled the car at McLaren Technology Centre in Woking.
"I think the car is probably the most refined-looking car we've had for some time now, so I'm very excited to get back into it," Hamilton said.
Blown diffusers are to be outlawed this year, so McLaren's focus has been on the rear of the car as they attempt to regain lost downforce.
Hamilton added: "Particularly the back of the car is a lot neater than it was last year. It's much, much tighter so the focus has been on making it as tight as possible to improve aerodynamics."
The new model's features also include distinctive sidepods and a much lower nose.
