The only multiple-use earplug with Conforming Material Technology" SmartFit uses body heat to adapt to the shape of the ear canal for a personalized fit. They are flanged to distribute pressure evenly on the ear canal ensuring solid protection and comfort all day. Economical reuse when regularly cleaned with soap and water for months of continued protection. Detachable corded earplug, HearPack® carry case or metal detectable style for food processing. NRR 25dB. Tested to ANSI S3.19-1974 standard. 100 pair per box. Sold by the box.