Engineering Ruler / Circle template

A small and very handy engineering ruler.
Features:
Circles in 10mm, 15mm and 20mm diameter
Radius of 15mm (half circle) and 20mm (quarter circle)
Straight edge of 50mm (without markings)

The dimension of the features are designed with 0,5mm mechanical pencils in mind. As you can see on the squared paper, they turn out pretty accurate.