Professional quality triangular scales are 6 sided with 12 sets of ratios. The three models cover most professional and student needs.

Ratios included are:

#402 - 1 ;100, 20, 250, 300, 400, 500.
#403 - 1:20, 25, 50, 75, 100, 125.
#409 - 1 ;25, 5, 10, 20, 50, 100.