EAR Classic® Foam Plugs are moisture resistant & will not swell. Foam will maintain its comfort, fit and critical recovery characteristics. Shape equalizes pressure throughout the ear canal as it expands; prevents shifting and keeps effectiveness of noise seal constant. Dermatologicaly safe foam is not irritating. Custom Fit every time. No sizing required. Reduces inventory of multiple sizes. Corded. 200 pair/box. Meets ANSI S3.19-1974.