The pattern drawing ruler from aluminium has a long side, 60 cm in length and a short side of about 23 cm. Point zero is exactly in the corner of the ruler which makes drawing a 90 degree angle and stopping at the right distance possible in one go without repositioning the ruler.
Aluminium retains it's shape, unlike wood that can warp. This ruler also works great together with a rotary cutter and cutting mat.

The rounded side of the ruler is used to draw the round edges of a pattern like for example hiplines, tops of sleeves and armholes. If the ruler doesn't have the correct shape, please consider using a flexible ruler.