1. Toward the end of the slide rule era many slide rule manufacturers produced "top of the range" models with a large range of general purpose scales. This is Aristo's contribution.

2. This rule is the largest general purpose rule I have being 6.5 cm (2.55 in) by 37.0 cm 14.5 in).

3. This rule has 31 scales, including a set of hyperbolic scales and a pair of Pythagorean scales (H2 and H1). The latter solve the function  Ö(1 + x²) and on this rule differ from the Q scale, for the same function on other rulers, in that the value of x is set on the D scale and the result is read on the H1, for 0.1 < x < 1, and H2, for 1 < x < 10, scales.

4. In some ways this is a successor to the Aristo 971 with the addition of two extra log-log scales and the H1 and H2 scales.