For years, the Classic® has been a proven performer. Slow recovery PVC foam provides comfort with low-pressure expansion. The E-A-R® Yellow color is your assurance of proven protection and high quality. The earplug is moisture resistant. The cylinder shape equalizes the pressure throughout the ear canal during expansion. This feature prevents shifting and keeps effectiveness of noise seal constant. Corded. Poly Pack. NRR 29dB. Tested to ANSI S3.19-1974 standard. 200 pair per box. Sold by the Box.