Comply N-100 Foam Noise Reduction Tips for Radio Communication (Black, Large, 3-tip Pack) Total Isolation: Communication in noisy environments is critical. Comply Foam Tips N-100 are perfect for in-ear two-way and listen-only devices, effectively blocking noise to funnel communication directly into the ear canal. Soft Comfort: Soft polyurethane foam is activated by body heat and becomes ultra soft, allowing for a secure fit that remains comfortable during extended use, reducing irritation and ear fatigue. Stay-In-Ear Fit:Patented "Dual Layer" technology dramatically increases retention during physical activities and provides a secure in-ear fit for today's most challenging high-noise law enforcement assignments Universal Fit:Comply Foam Tips N-100 feature a universal fit for any acoustic tube barbed adapter.