Dr. Denim Echo Jeans in Blue. - size 31 (also in 25, 26, 27, 28, 29, 30) Dr. Denim Echo Jeans in Blue. - size 31 (also in 25, 26, 27, 28, 29, 30) 99% cotton 1% elastane. Machine wash. Zip fly with button closure. 5-pocket styling. Light distressed details at hem. Structured denim fabric. 18 at the knee and 18 at the leg opening. DRDR-WJ205. 2010108L40. Keeping faith in the theory that every day is a denim day, Dr. Denim is a Gothenburg, Sweden-based fashion label that values the power of the perfect pair of jeans. By combining functionality, affordability and fashion, the brand's expansive collection includes not only high-quality denim garments, but comfortable, non-denim closet staples to flawlessly match.