Laminated B-681 polyester seals in and protects graphics. Industrial grade self-adhesive protects against bacteria or moisture trapping behind the pipe marker. Style 3C pipe markers measure 2-1/4 in. x 2-3/4 in., come with three markers per card and fits 3/4 in. or smaller pipe diameter. All stock markers meet ASME ANSI when used with arrow tape. For clean room applications, the material liner should be removed prior to entering the clean room.