Note: The add-on radio adapters are required if you plan to use the Echo Bridge with a radio. Motorola radios require a specific Motorola adapter and simpler radios (such as the the Rocky Talkie) require the Kenwood 2-Pin Adapter. Since not all users need both we offer them as options. Please visit the connector's page to determine compatibility. Please let us know if your radio isn't listed! Note2: Currently Bridges are made to order. Expect about a 1 month turn around time. Motorola M7/M11 Adapter Kenwood 2-Pin Adapter Echo Bridge – Field Audio Integration Kit The Echo Bridge is a portable, field-ready audio interface designed to bridge communication between legacy field phones, modern cell phones, and wireless radios. Developed for cave rescue operations, it enables seamless communication between otherwise incompatible devices. It also acts as a field phone, allowing operators to communicate with anyone on the 2-wire network. At its core, the Echo Bridge allows rescuers deep underground, using traditional field phones—like the TP-6N—to connect directly to a radio system at the cave entrance. Once connected, their messages are automatically transmitted over a selected radio channel, enabling critical updates to reach incident command or other teams instantly. Cell phone capability allows for direct communication from rescuers deep in the cave to anyone in reach of a phone, such as a local hospital medical director. Compatible with: Field phones using two-conductor wire like the TP-6N field phone. Wireless radios Motorola APX series radios Kenwood 2-pin style interface (such as the Rocky Talkie) Most smartphones via the with included adapters for USB-C and Apple Lightning Any TRRS style headset/handset that use a 1/8" or 3.5mm plug Each kit includes: Waterproof carrying case Echo Bridge device 2x Panasonic 18650 batteries Field handset Radio adapter (Select desired option USB-C and Apple Lightning adapters 3.5mm-to-3.5mm TRRS aux cable Instruction manual Built for reliability in harsh environments, the Echo Bridge brings legacy and modern communication together—making it ideal for technical rescue, search & rescue (SAR), disaster response, confined space, and subterranean communications.