iSeries Waterproof Wireless Four Mic Case The 3i-1813-5WMC Wireless Mic case is part of the Waterproof Series of cases with a custom foam interior to protect a variety of brands including Shure and Sennheiser mics to name a few. The custom foam interior is designed to cradle each mic and will fit up to four handheld wireless microphones, four wireless body pack transmitters and accessories. Convenient finger holes to quickly grab the microphone and easily slide in the body pack transmitters. iSeries 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, 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.