This ruler is specially designed by Aquino da Silva, a pen holder maker, and Belinda Chim, a well-known professional calligrapher based in Macau.
Calligraphy Guideline Ruler
Size: 2/3 size of a credit card. 10.5 cm (L), 4.25 cm (W), 0.15 cm (H)
X-heights from 3 to 7 mm, with a 55-degree slant angle.
X-heights of 1, 1.5, 2, 2.5 and 3mm, with a 52-degree slant angle.