Boots Ringplan 5" Standard Slide Rule. Made in Japan. Probably made by Jakar; it is very similar to the Jaker 523A below.
Boots Ringplan 10" Standard Slide Rule. Made in Japan. Probably made by Jakar; it is very similar to the Jaker 1003A below.
Boots Ringplan 5" Precision Log Log Slide Rule. Made in Japan.
Boots Ringplan 10" Precision Log Log Slide Rule. Made in Japan.
Skol Forlaget Gavle AB. Loosely translated this means Gavle School Publisher. AB stands for Aktiebolag the Swedish equivalent of Ltd, Limited Company. There are no other makers marks on this rule but the design of the box and the rule looks Japanese to my eye.
Helix U 02.
Hellerman 51. This is very similar to my Jakar 1005 hence my reason for placing this rule in the Japanese section.
Jakar 29 Student Log/Log.
Jakar 55 Rietz.
Jakar 66 Electro.
Jakar 88 College Duplex.
Jakar 523A
This slide rule has no country of origin or maker's mark however it is very similar to the Jakar 523A hence its inclusion here.
Jakar 1003A
Jakar 1005
Jakar 1006D
Jakar 1011.
Jakar 1013.
GB, Kawai Laboratory, Tokyo.
Teknor Slide Rule, sourced from Sweden. This slide rule has no maker's marks but it arrived in a box marked Teknor. This box is identical to those housing the Technical Sales slide rules below. For this reason I am tentatively of the opinion that it was produced by Uchida Yoko.
Uchida Yoko Technical Sales Emblem Series Tutor 1051
Uchida Yoko Technical Sales Emblem Series Tutor 1051 without the K Scale.
Uchida Yoko Technical Sales Emblem Series Olympic 1052
Uchida Yoko Technical Sales Emblem Series Olympic LL 1053
Uchida Yoko Technical Sales Emblem Series Commercial 1071
Uchida Yoko Technical Sales Emblem Series Techlog 1081
Uchida Yoko Technical Sales Emblem Series 1091. The scale set on the reverse side is similar to the Yokota scale set patented by Seinan Yokota, Assistant Professor of Naval Architecture at the College of Engineering, Imperial University, Tokyo, Japan in 1907 and consists of LL3 LL2 LL1 A/B K C/D LL01 LL02 LL03 with S Sec T on the reverse of the slide.
