The R171 SLK is the second-generation SLK-Class, produced from 2004 to 2011. It built upon the original R170 with a more aggressive design, stronger performance, and more modern technology—while retaining the signature Vario-Roof retractable hardtop.

The vehicle had a facelift in 2008. The pre-facelift models were fitted with NTG1 systems and the facelift models with NTG2.5 systems.