AJ-10TD tribrach with adapter AL-1 is used for centering and leveling the RTK receiver. It has a spirit level for leveling and, when viewed through the hole on the side, an optical “bullet” that shows the exact location of a point on the ground below it. The device weighs 1.4 kg and is compatible with a standard tripod with a 60 mm hole in the center and a hollow 5/8″ mounting screw.