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. It will not absorb moisture and swell. The foam plug will continue maintaining its comfort, fit and critical recovery characteristics. The cylinder shape equalizes the pressure throughout the ear canal during expansion. This feature prevents shifting and keeps effectiveness of noise seal constant. The breakaway-corded version protects wearer in case of machine entanglement. Pillow Pack or poly bag packaging available for uncorded style. Available corded or uncorded. NRR 29dB. Tested to ANSI S3.19-1974 standard. 200 pair per box. 10 boxes