Sacha London Martina Black Nappa at Robert Frost and www.frostshoes.com. This gorgeous pump has a leather upper, synthetic lining, and a manmade sole. This beautiful 4" heel has a 1.5" covered platform to add extra height and comfort for any woman. The Sacha London Martina in Black Nappa runs true to size at Robert Frost Fine Footwear and www.frostshoes.com.