The Limited Edition Levi's x Clot UNIONRAIL 501 jeans have been made in commemoration of the contribution made by the Chinese in United States during the 19th century. The Transcontinental Railroad which connected east and western United States was was built by the Central Pacific Railroad of which 90% of the employees were Chinese. The workers wore a denim work outfit because of the durability of the fabric and these jeans have been customized to show signs of wear such a paint, grease and rips similar to those that would have been seen on the orginal railroad workers. The thread used in the stitching is red and gold which are the colours of good luck in China. These jeans are only available in Hong Kong and Taiwan.