Max offers superior noise-blocking performance in a single-use earplug. Max's enhanced contoured shape is easier to insert and resists backing out of the ear canal, while its softer foam delivers superior longwearing comfort - delivering solid performance that your workers can depend on. The smooth, soil-resistant skin helps prevent dirt from penetrating the surface prior to insertion. Refill for Leight® Source 500. NRR 33dB. Tested to ANSI S3.19-1974 standard. 500 pair per box. Sold by the box.