1. This rule looks very similar to the Hemmi 2664S but when examined closely there are a large number of differences.
   • This rule has an Inch scale along the top beveled edge.
   • This rule does not have a CIF scale on the front of the slide.
   • The Centimetre scale along the bottom edge does not fold (13-0-13) as in the Hemmi 2664S edge but runs from 0-27 and is closer to the edges on this rule.
   • This rule does not have a L scale on the back but instead an additional SI scale
   • The plastic insert sheet is held loosely in place whereas on the Hemmi 2664S it is fixed in place by a small screw.
   • This rule is 1.1 cm shorter.
2. There are no date codes on this rule so it probably dates from around the time of the introduction of date codes but after Hemmi dropped the "Made in Occupied Japan" description on their rules.

Brand	Hemmi
Model	2664
Country of Manufacture	Japan
Date of Manufacture	No date code on rule - c 1950
Scales Front	K, DF [CF, CI, C] D, A
Scales Back	[TI1, TI2, SI2, SI1]
Number of Scales	11
Slide Rule Materials	Bamboo/Celluloid
Cursor Materials	Metal/Glass
Cursor Lines	1 Front, 2 Back
Scale Length	25 cm
Length	28.4 cm
Width	4 cm
Condition	Good, Cursor spring is weak
Documentation	None
Accessories	Heavy cardboard two part slip case