Integrated, Intra-Squad Radio
The Integrated, Intra-Squad Radio (IISR) is a secure handheld 2-way radio, produced by Motorola for the US Marine Corps. Its intended purpose is squad-level communications during urban warfare. The USMC ordered 60,000 radios to be used until replaced by the more complex Joint Tactical Radio System (JTRS) cluster 5 spiral 2 radio in 2013. However, JTRS was cancelled in October 2011. The IISR is similar in form and function to a Motorola XTS 2500i with embedded encryption module, which was essential to provide secure voice communications, especially in war zones.

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Military radio systems of the United States
United States Marine Corps equipment