Tri-partite aluminium ruler, 300 cm

Aluminium ruler for accurate measuring in mm of the planeness of bare surfaces such as asphalt, concrete, gravel, floors of sports accommodations, etc.
The overall length measures 3 meter, the range is 1-20 mm and the accuracy is 0.3 mm. The aluminium ruler consists of three parts. Standard set, including measuring wedges and carrying bag.