Mercedes-AMG has announced another addition to its GT family – the AMG GT S Roadster becomes the third open-top, two-door variant in the line-up, sitting in between the GT Roadster and GT C Roadster. It also brings the number of GT offerings from Affalterbach to 12, the range consisting of four two-door coupes, three roadsters, two customer sports racing cars and three four-door coupes.

Like its siblings, the GT S Roadster features AMG’s handbuilt 4.0 litre V8 biturbo M178 mill, and output is identical to that on the GT S coupe. Revised in an 2017 update, the unit offers 515 hp (or 522 PS) at 6,250 rpm and 670 Nm at 1,900 to 5,000 rpm in this application. Paired with a seven-speed AMG Speedshift DCT 7G transmission, performance figures include a 0-100 km/h sprint time of 3.8 seconds and a 308 km/h top speed.

Standard equipment includes an AMG performance exhaust system, Airpanel active air management system, AMG Ride Control suspension with adaptive damping and 19-inch alloy wheels (20-inch at the rear). Also on, LED high performance headlights and an electronically-controlled locking differential at the rear axle.

Inside, the GT S Roadster comes with sports seats in black Artico man-made leather/Dinamica microfibre and an AMG Silver Chrome Interior package as standard – the latter dresses up the centre console surround, air vent bezels and trim strips in the door armrests in silver chrome. As for the three-layer fabric roof, it’s available in a choice of three colours – black, beige or red.

As usual, plenty of customisation options for the car, and for trim the list includes an exterior carbon-fibre package, nappa leather upholstery in a variety of colours, AMG Performance seats and an Airscarf neck-level heating system.

Mechanical options meanwhile include an AMG Dynamic Plus package, which adds on dynamic engine and transmission mounts and a firmer and specifically-tuned suspension. An AMG rear axle steering can also be selected with the package. Also available on the options list is an AMG high performance ceramic braking system.