ReadyMax PermaPlug earplugs provide hearing protection and comfort. A 2 piece co-molded design uses 2 different material durometers (hardness) to achieve ultra-comfortable, soft fit with a stiff core for easy insertion and a triple flange design insures proper fit. Environmentally friendly, PermaPlug ear plus are washable, reusable and recyclable. PermaPlug earplugs are easy to screw on/off for replacement on ReadyMax safety products. Noise protection: NRR 25/SLC80 18, Class 3/SNR 29.