Notes: "Here are three very small slide rules, each with scales 10 cm (4”) long. The first is an Aristo “Puck”, the second a Post (Hemmi) 1441, and the third is an A. W. Faber model 389. Completeness varies: the Faber 389 is a naked slide rule, the Post comes with a leather case, and the Aristo Puck is brand new in the box with pocket case and instructions (in German, copyright 1954). The Puck wins the scales sweepstakes with 9 scales total, including CI and K scales. The Post gets second place with 8 scales, losing the K scale. The Faber is in third with 7 scales, missing the CI and K scales. However, the Faber is the only rule here with a 3-line cursor, and the Post has a magnifying cursor and is also marked “Made in Occupied Japan”, dating it to the immediate post-war period. "