NOBEX Octo Folding Square Features:

An ingenious square! Often overlooked, it features an anodised aluminium handle with a stainless steel blade, which has measurements etched for ling life and painted for easy reading.
The benefit of this square is that the blade can be moved to measure every 22.5 degree angle over a 180 degree range.
That's eight angles on the one square - hence the name - Octo.
It is guaranteed to be accurate to 0.06 degrees on all settings and hold the accuracy over 12,000 cycles.