Specifications include, but are not limited to: Single Desktop Charger (FAA9100-621) Carrying Pouch (FAA9100-302) Speaker Mic with Throat Mic (FAA9100-411) Single-Ear, Behind the Head, Push to Talk (FAA9100-419) Designed to operate with Sentinel handsets Can be worn with traditional hard hat and helmets Noise-cancelling, flesible boom microphone Single-ear speaker Inline Push-to-Talk (PTT) button with a 2.5mm jack for removable fingertip remote PTT accessory Built to US Department of Defense, MIL-STD-810 standards Adjustable padded frame Portable Mesh Node with Charger (FAA4215-050) Self-configuring network Battery operated: > 40 hours Lightweight: < 6.5 kg Small: 30cmW x 13cm D x 23cm H Communication range up to 750m Directional Antenna (Dual-Yagi Assembly) for Portable Mesh Node In-line directional antenna Dual, high-grain elements attached to arms Arms fold for transport and raise and lock in place while in use Attaches to Sentinel Portable Mesh Node or Gateway Omni Antenna (Flex Disc) for Portable Mesh Mode Directional disc antenna with flexible rugged arm Connects to Sentinel Portable Mesh Node or Gateway Other: System must meet MSHA Certifications - MSHA 30 CRF (Intrinsically safe for methane/air mixtures) Vendor providing equipment must be able to provide technical support by phone 24/7/365. System must be interoperable and compatible with the MSHA mine rescue communication system.