Rails Sinclair Button Down Shirt in Blue. - size M (also in S) Rails Sinclair Button Down Shirt in Blue. - size M (also in S) 100% cotton. Made in China. Machine wash. Front button closure. Poplin fabric with tonal stitching detail. RAIL-MS218. RM-632A-948C-1570. Launched in 2006, Rails is a unique brand of fashion fusing California comfort activewear with European styling. High quality fabrics, narrow cuts, and unique lines; this collection is influenced by international travel and metropolitan lifestyle.