Daimler-Benz AG introduced the Mercedes-Benz 190 SL in February 1954 at the International Motor Sport Show in New York. It was designed as a touring sports car „which owing to its high comfort is intended for a class of customers who want to travel large distances themselves at high cruising speeds in this externally very sporty looking car,“ as design engineer Josef Müller wrote in retrospect in 1957 – that can be said of every SL series since.

W 121 series (1955 to 1963)
• Modern four-cylinder with overhead camshaft
• Modern chassis for high ride comfort and great safety
• Retractable roadster soft top

W 113 series (1963 to 1971)
• Folding soft top operated with the greatest of ease
• Six-cylinder engine with six-plunger injection pump
• Automatic transmission available in an SL for the first time
• Safety body with stiff passenger cell and deformable front and rear segments
• Numerous other safety features such as an interior designed to reduce injury hazards in accidents and a buckling steering column
• Disc brakes on the front wheels, from 1967 also on the rear wheels

R 107 series (1971 to 1989)
• Further developed safety body
• Frame-floor unit with differing metal thicknesses to produce a carefully defined crumple pattern
• Sturdy roll-over protection: high-strength A-pillars and windscreen frame with bonded glass
• Special air ducting on the doors ensuring reduced soiling of the side windows and mirrors
• Contactless transistorised ignition, Bosch K-Jetronic, hydraulic valve play compensation (1975)
• First SL with catalytic converter (1985)

R 129 series (1989 to 2001)
• Automatic roll-over bar (deploying time: 0.3 seconds)
• Extremely sturdy integral seats
• Coefficient of drag 0.32 (with hardtop)
• Fully automatic electro-hydraulic folding soft top
• World premiere of the draught-stop
• Adaptive Damping System ADS (optional)
• Fixed-calliper disc brakes
• First twelve-cylinder engine in an SL (1992)
• Electronic Stability Program ESP® (1995)
• Brake Assist BAS (1996)
• Cruise control effective even in 30 km/h zones (1996)

R 230 series (from 2001)
• Vario-roof with ingenious swivelling mechanism and 16 seconds folding time
• Sensor-controlled roll-over bar fully operable even with the vario-roof closed
• Electro-hydraulically controlled braking system Sensotronic Brake Control (SBC™)
• Suspension with Active Body Control ABC
• New type of head/thorax airbags in the doors
• Coefficient of drag 0.29 (closed vehicle)
• Use of lightweight components for best fuel economy

Source: Daimler AG