Made in Germany. (probabley Faber & Castell ?)

W1-W2, W1'-W2' scales (square Roots, same as R1-R2) show an effect of double length (50cm, 20inch).

Include good scales:
P (Pythagorean, sqrt(1-X²) ) scale,
red complementary angles and T1-T2 (extended tangent) scales.

It has only 24 scales and missed LL0, LL00, and A-B scales compared to other good slide rules.