'Every age and social class'
"The butt-lifter and the design go hand in hand," says Nayibe Gaitan, who has been working for 11 years in this industry. She is now a saleswoman for a brand in Gran San shopping centre, but before that she worked in the administrative department of the factory, so she knows this world well. According to her, women from every age and social class buy the decorated butt-lifters. The company she works for manufacture some 350 units of every model (50 models per collection) and they never repeat them - when they are gone, they are gone. Almost no brand in this place repeats a model. In Gran San wholesale jeans are between 40,000 and 60,000 Colombian pesos apiece $14-20, £11-15). The decorated butt-lifter has become the archetypical Colombian jean, a product that has reached markets outside the country. "Any Latin woman wants her butt-lifter trousers," says Mr Rivera. "A client of mine in the US sells to Latinas all over the world."