Light metal rectangular profile with removable end caps 2 vertical and 1 horizontal vial with rare earth magnet system measurement accuracy in normal position 0 029 degrees 0 5 mmmoverhead measurement 0 043deg 0 75mmmextra strong light metal rectangular profile with ridges for gripping and novel removable end capsmade from two materials these end caps provide increased damping and when removed a cleaner marking line right into the corner length 200cm 80in