The McLaren M23, designed by Gordon Coppuck, was extremely successful and remains one of McLaren's most iconic racing cars. Introduced in 1973 the M23 was still raced as late as in 1978. Many chassis were built and some were sold to customers who continued to race the M23s in non-championship Formula One races successsfully for many years. The M23 had a wedge shaped nose and a complete engine and gearbox cover combined with the air intake box. The radiators were positioned on either side of the cockpit. To comply with the new safety regulations regarding deformable structures the monocoque had inner and outer skins of 16-gauge aluminum with foam injected between them. The chassis featured rising rate front suspension with tubular double wishbones and upper links extended inboard, operating the coil spring/damper units. Rear suspension was by reversed lower wishbones, single upper links, twin radius rods and outboard coil spring/damper units. Of course the M23 was continually further developed to keep it competitive, with revised rear wings, modified airboxes and side pods, a longer wheelbase, revised track dimensions and relocation of the oil coolers among the most important modifications. Emerson Fittipaldi clinched the 1972 Drivers' World Championship in an M23, and in 1976 the M23 allowed James Hunt to become World Champion. Its successor, the McLaren M26, took a long time to be developed into a race worthy car, and was not nearly as successful as the M23 had been.