CLK models have three-point seatbelts and head restraints for all occupants, two-stage adaptive front airbags and side airbags in the front and rear doors. Its structural design has focussed on frontal and side impact protection, while accident-prevention systems such as anti-lock brakes, brake assist and ESP stability control are standard across the range. The front seats have seatbelt pretensioners and outer rear seats buckle-type belt tensioners, with all outboard positions benefiting from the addition of belt force limiters and belt height adjustment.