The Porsche sports car pictured here in this Nicolas Hunziker 19 x 27 inch poster, painted in 2012, is a Porsche 908 LH, #25, as driven to victory in the Spa 1,000 km race in 1969 by Brian Redman (still alive and very active in organizing historic sports car races) and Jo Siffert (died in an F-1 race in 1971 at Brands Hatch, England).
Porsche driver Brian Redman signed it with a black Sharpie pen on the right side. It's a very clear signature. The main color is a medium green, with white as the main color of the Porsche, and with green trim all-around.