For an American manufacturer of excavators, a counter weight of 10 tons needs to be assembled to the back of the 'house'. Four M36 bolts are precisely tightened vertically from the underside at 2800 Nm each. As a result, the counter weigth can't fall off and withstands the high vibrations encountered in use. We developed a mobile tightening solutions with an integrated industrial computer for traceability, using a WiFi connection to the plants network database.