3" x 6" x (0.3mm thin) This is a genuine shell in a subway design size. SeaShell Laminate Subway Self-adhesive back tile is designed for interior use only. The laminate tile is laser cut to subway size. The genuine shell is created by a proprietary process which is then uniquely applied with a self-adhesive backing. The laminate tiles are then coated with a high gloss, fire rated two-pack polyurethane for protection and stain resistance.