An operator with offices in Ushuaia and El Calafate, selling 4x4 trips to Lago Escondido and Fagnano, the Laguna Esmeralda trek, the national park and Beagle Channel navigations.
The number below is the one their site marks as the Ushuaia WhatsApp, and it matches the tourism secretariat's register. The El Calafate office has its own number, on their site.