The 3i-1711-SEW the Sennheiser EW Wireless Mic in a very compact case and is part of the 3I Waterproof Series of cases. This case fits the Sennheiser EW100 Series Wireless Microphone Systems. 3I Series injection molded waterproof cases are constructed of ultra high-strength polypropylene copolymer resin and feature a gasketed, waterproof and airtight, submersible design (IP67) that is resistant to corrosion and impact damage. Its molded-in hinge, patented "trigger release" latch system, comfortable, snap-down rubber over-molded cushion grip handle, secure stacking, and automatic ambient pressure equalization valve (MIL-STD-648C) all contribute to its military grade design. The custom cut PE interior foam is designed to securely transport the entire Sennheiser EW Wireless Microphone package; the receiver, antennas, handheld mic transmitter, body pack transmitter, lavaliere microphone, mic clip, power supply, a spare set of AA batteries and additional accessories with an interior measurement of 17” x 11.5” x 6”. - Ultra high-strength polypropylene copolymer resin - UV, solvent, corrosion and fungus resistant (MIL-STD-810F) - Complete gasket seal makes these cases absolutely watertight (MIL-STD-C-4150J) - Automatic ambient pressure equalization value (MIL-STD-648C & IP67) - Resistant to corrosion and impact damage - Molded-in hinges - Patented "trigger release" latch system - Rubber over-molded cushion grip handle - Custom cut foam to accommodate a complete Sennheiser EW Wireless Mic