Dual protection is often a requirement in many critical working areas where exposures may exceed 95 decibels (dBA) Intrinsically Safe: Based on the existing SM1P-IS headset and incorporating our unique dual protection feature; the SM1P-ISDP Headband (Over-the-Head) headset fills the marketplace need for a high performance intrinsically safe headset for extreme noise environments that require UL/CSA/TIA certifications with the highest NRR ratings in the industry. It’s the perfect solution for your extreme high noise and hazardous environments such as explosive chemicals and fuels as well as combustible powders; SM1P-ISDP: TIA-4950-A, CSA C22.2 No. 157.92, UL 913 5th Edition !!Cable connection to a Two-Way Radio available (cable sold separately: SRCK61XXCR01 series)Features; Connect to two-way radios via Bluetooth or cable; Connect to intrinsically safe mobile devices (HFP, HSP and A2DP profiles) via Bluetooth; Up to 30 db NRR (Noise Reduction Rating) / 37 dB SNR / 32 dB, Class 5 SLC80; Clear communication up to 120 dB noise levels with Noise-Cancelling boom mic.IS: (UL/CSA/TIA) approved; Headset to Headset PTT communication (approx. 50m / 150ft range) via Short Range; Talk 'face to face' in high noise (No need to remove your headset or move to a quiet area), SENS Technology (Enhances speech while suppressing background noise to a safe level), Programmable Volume Limiter (Limit 'in-ear' noise exposure to 82dB); Retain 360° situational awareness (Remain aware of surrounding noises and hazards); VOX capable; Built-in rechargeable battery (lithium-ion, 18 hour battery life, 4-hour charge time); Rugged and lightweight design; USB for programming allows simple configuration of the headset and software updates.