NSF Lesli Shirt in Blue. - size S (also in ) NSF Lesli Shirt in Blue. - size S (also in ) 100% cotton. Front button closure. Chest flap pockets with button closures. Patchwork detail. Frayed trim. Shirttail hem. Buttoned cuff sleeves. NSF-WS204. 2462 ICH. Based out of California, NSF has caught the eye of many. With their clean design and boyish charm, NSF is recognized for its relaxed, modern style looks.