Versatile plugs provide great protection at an excellent cost savings. Dual-size design ensures a solid fit for all, simplifying your inventory concerns. Self-adjusting polyurethane foam expands gently, creating a low-pressure ear-canal barrier. Closed-cell foam skin delivers superior soil resistance. Corded/Cordless: Cordless; Shape: Pill; Material(s): Polyurethane Foam; Noise Reduction Rate (NRR): 31 dB.