Rails Perci Sweater in Gray. - size S (also in ) Rails Perci Sweater in Gray. - size S (also in ) Wool blend. Dry clean only. Intarsia knit fabric. Rib knit trim. RAIL-WK15. 816 336 491. 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.