SureFire Hearing Protection Comply Canal Tips are the official replacements for the disposable memory-foam tips used by EP7 Sonic Defenders Ultra and EP10 Sonic Defenders Ultra Max earplugs. When installed correctly and worn as directed, these body heat-activated foam tips, tapered for deeper insertion, conform to your ear canal and maintain an acoustic seal, providing a Noise Reduction Rating (NRR) of 28 dB* when used with EP7s and 30 dB when used with EP10s.* Constructed of ultra-soft polyurethane foam, Comply Canal Tips provide all-day comfort and help reduce irritation and fatigue in the ear canal. Their elastomeric cores feature molded-in threading that makes tip replacement (recommended every 2-4 weeks or when soiled) simply a matter of unscrewing the old tip from the stem and securely screwing on a new one.