High NRR plugs offer superior noise-blocking performance. Contoured cylindrical shape design provides excellent ear-canal fit with improved back-out resistance. Soft, expanding polyurethane foam ensures a comfortable fit. Soft, soil-resistant closed-cell foam skin protects against dirt buildup. Wired/Cordless: Drill; Shape: Bell; Material(s): polyurethane foam; Noise reduction rate (NRR): 33 dB.