The HEDUE framing square is made of stainless spring steel. The stainless steel is spotwelded at the corner (4 clean, flat-ground, spotwelds) and is has an unusual level of accuracy and quality for this type of tool.
HEDUE's manufacturing standard for these squares is the right angle cannot be off more than 0.005 mm per centimeter of length. So for the 60 cm square, that works out to 0.3 mm, and for the 1 meter square it is 0.5 mm.
The arms measure 35 mm by 1.2 mm, and 2.5 mm at the welded corner overlap.
The short arm of the square has marking holes spaced at 5 mm.
The long arm features an easy-to-read scale both inside and outside.
See the enlargement to have a closer look at the details.
Four sizes available.