Smaller Diameter - Ideal for workers with smaller ear canals, including women. Low-pressure Polyurethane Foam - Expands gently for comfortable long-term wear, eliminates feeling of ldquo;tightnessrdquo; in ear canal. Contoured T-Shape - Aids in easy insertion, removal from ear canal. Pack of 500 Honeywell Maxlite Ls500 Refill Pack (500 Pairs)