Concise Slide Rules
and rebranded variants

This gallery is focused on the varieties of Concise circular slide rules and the many variants of promotional specimens. Concise is manufactured by K.K. Konsaisu of Tokyo, Japan, and is the only manufacturer still producing and marketing new slide rules that have the classic scales. It appears that Concise promotion slide rules were only sold to United States companies. The advantage of circular slide rules, is that the dimensions can be small enough to fit in your shirt pocket, yet have the scale resolution of a standard linear slide rule. Construction is simple as the only only fastener is the single screw or rivet at the center of the disk. A few Disk Charts are ahown which logarithmic scales or of unusual construction.

KEEP ISRM FREE!



C06 Lietz 3625-20 8.4cm
Lietz 3625-20 8.4cm Dia
Made in Japan
Front Scale
D ( C, CI, A, K )
Back: equivalents


REF SIC 120 (Version 2)
SIC 120 (Version 2) - 1962
Made in Japan for Scientific Instruments Co. - 10.8cm Dia
Front Scale
K, A, D ( C, CI, E1(spiral) )
Back Scale
L, DI, D T, S, T, S, T, TS
Archive - Ted White Collection


REF Concise SIC 300B
Concise SIC 300B - 1961
Made in Japan by Concise for SIC- 11.2cm Dia
Front Scale
K, A, D ( C, CI, B, L )
Back Scale
LL3, LL2, D ( C, S Cos, T1 Cot1, T2 Cot2, ST
Archive - Ted White Collection


C11 SIC 250
SIC 250 - Patent 440028
Made in Japan for Scientific Instruments Co. 1962 - 8cm Dia
Front Scale
K, A, D ( C, CI, L )
Back Scale
D, T, S, T<45, S<45, T&S<5.8


REF SIC 1610-D
SIC 1610-D
Made in Japan for Scientific Instruments Co., 1963 - 12.8cm Dia
Front Scale
LL3, LL2, LL1, LL0, K, A, D ( C, CI, B, EI(spiral) )
Back Scale
LL03, LL02, LL01, LL00, P, L, DI, D ( C, T, S, T, S, T, TS )
Archive - Ted White Collection


REF Star Sliding Disk 130
Star Sliding Disk 130 - 10.8cm dia
Made in Japan
Front Scale
K, A, D, ( C, CI, EI (spiral))
Back Scale (Trig scales in Degrees-Minutes-Seconds)
L, DI, D, T, S, T, S, T, TS
Archive - Ted White Collection


General Electric - Defense Electronics Division

ISRM 09.10.21.10
General Electric - Defense Electronics Division
Made in USA - 2-1/2" x 4"
Front Scale
D ( C)
Side Edges: CM and inches scale
Donated by Marten C. Jensen


C08_Otis Engineering Gas
Otis Engineering Gas Calculator
Made in Japan by Concise - 8.4cm Dia
Front Scale
D ( C, CI, A, K )
Back: Gas and Fluid weights


C12 Pacemaker
Pacemaker
Made in Japan by Concise- 8.4cm Dia
Front Scale
D ( C, CI, A, K )
Back: Conversions


Concise 28N Motorola Semiconductors

ISRM 09.10.21.11
Concise 28N Motorola Semiconductors
Made in Japan by Concise - 8.4cm Dia
Front Scale
D ( C, CI, A, K )
Back: Conversions
Donated by Marten C. Jensen


ISRM Concise 28
Concise 28
Made in Japan by Concise - 8.4cm Dia
Front Scale
D ( C, CI, A, K )
Back: Conversions


C27 Alpha 4028 (Concise 28)
Alpha 4028 (Concise 28)
Made in Japan by Concise - 8.4cm Dia
Front Scale
D ( C, CI, A, K )
Adv: Westeel-Rosco and Takeda
Front 387Kb
Back 420Kb


REF Concise 28N
Concise 28N
Made in Japan by Concise - 8.4cm Dia
Front Scale
D ( C, CI, A, K )
Back: MKS/CGS conversions for Velocity, Pressure, Flow Rate Length, Area, Weight, Volume, Power Energy & Heat, Temperature Conversion, Density
Archive - Art Kautz Collection
Manual 1.67Mb


REF Concise 28N

ISRM 13.01.09.01


Michael P. Maloney


Manual 2.24Mb PDF
Concise 28N
Made in Japan by Concise - 8.4cm Dia
Front Scale: D ( C, CI, A, K )
Back: Equivalents, alternative artwork than the previous 28N, mostly linear units.
Sleeve: SRL - System Research Laboratories, Inc. Dayton, Ohio
Donated by Michael P. Maloney
Michael P. Maloney finished pre-engineering at Niagara University in 1965 and graduated as an Electrical Engineer in 1968 from the University of Detroit. He also attended George Washington University and received a Master Degree in Engineering Management in 1978. After graduating from the University of Detroit, he joined the Department of Defense (DoD) and retired as a Technical Director in 1997. While working for the DoD, Mr. Maloney had three tours in Europe totaling 13 years. Mr. Maloney used the ten different types of slide rules or slide charts in the design, development, installation and maintenance of communication and radar systems. These have been donated to ISRM. Mike writes: "Of particular interest to me is the shirt pocket SRL circular slide rule and my white plastic 'nerd pack' (shirt pocket protector). These two items traveled with me on all my TDYs (business trip) while stationed in Europe during the 'Cold War'." Upon retiring from the DoD Mr. Maloney worked for Raytheon, Applied Signal Technology, Conquest, Boeing and Hayden Software Consulting. Mr. Maloney has five patents and enjoys wood working, traveling, reading and developing algorithms for solving cryptograms.


C32 Lafayette F-382 (Concise 270)

Lafayette F-382 (Concise 270)
Made in Japan by Concise - 11.2cm Dia
Front Scale
L, D ( C, CI, A, K )
Back Scale
DI, D ( S, T1, T2, ST )


C29 Concise 270N
Concise 270N
Made in Japan by Concise - 11.2cm Dia
Front Scale
A, D ( C, CI, B, K, L )
Back Scale
DI, D ( S Cos, T1 Cot1, T2 Cot2, ST )


Concise 271

ISRM 13.06.28.01

Concise 271
Made in Japan by Concise - 11.2cm Dia
Front Scale
L, D ( C, CI, A, K )
Back Scale
DI, D ( S Cos, T1 Cot1, T2 Cot2, ST )
Gift Of Susan Jackson, Boulder, Colorado, daughter of Jim Rodgers

Jim Rodgers (1929-2012) used this slide rule (and others found within ISRM) during his career. He was a Naval Aviator and had training at the the Nuclear Weapons Training Center - Atlantic (c1968). He later resided in Boulder, Colorado. He was married to Ceil Rodgers for 63 years and had four children, Jim, Susan, Cathy and Stephen, and eight grandchildren. An avid reader, progressive thinker, political junkie, problem solver and perpetual optimist, Jim was loved and admired by everyone who knew him. Jim donated his body to science.


REF Concise 300
Concise 300
Made in Japan by Concise - 11.2cm Dia
Front Scale
K, A, D ( C, CI, B, L )
Back Scale
LL3, LL2, D ( C, S Cos, T1 Cot1, T2 Cot2, ST )
Archive - Art Kautz Collection


Concise 320 with Calendar

ISRM 12.06.24.02
Concise 320
Made in Japan by Concise - 9.7cm Dia
Front Scale
D ( C, CI, A, K )
Back Scale
Unit Conversions ( Calender - shows years 1968 through 1981)
Donated by the Huang family.
The collector, who prefers to remain anonymous, obtained a B.S. degree in Physics from Taiwan's National Tsing Hua University in 1971. His love for computation has encouraged him to build a collection of slide rules, HP and TI calculators, as well as abaci, many displayed at ISRM.


REF Concise Type-E Weights and Measures Conversion Tables Data Computer
Concise Type-E Weights and Measures Conversion Tables Data Computer
Made in Japan by Concise
Front Scale: 4-3/8in || D ( C, CI, A, K) || 11cm
Insert: Conversions for Flow, Pressure, Energy, Power, Volume, Velocity, etc.
Scans donated by Kip Ryan

3.8MB PDF


C18 Concise Master Builders Type-E Data Computer
Concise Master Builders Type-E Data Computer
Made in Japan by Concise
Front Scale: 4-3/8in || D ( C, CI, A, K) || 11cm
Insert: Conversions for Flow, Pressure, Energy, Power, Volume, Velocity, etc.


Sama & Etani/Concise EE-112 Reactance Slide Rule

ISRM 09.11.16.01
Sama & Etani/Concise EE-112 Reactance Slide Rule - Copyright 1966
Made in Japan by Concise, Designed by Sama & Etani Groton, Massachusettes
Front Scale: 4in || D ( C, CI, L, S Cos, T1 Cot1, T2 Cot2) || 10cm
Back: Reactance Nomograph
Insert: Conversions for Flow, Pressure, Energy, Power, Volume, Velocity, etc., Resistor Color Codes, Copper Resistance
Donated by Jason A. McHenry, Tucson, Arizona
Instruction Manual 1.67MB


Sama & Etani/Concise CTCS-552 Slide Rule (NUPRO)

ISRM 13.08.27.03
Sama & Etani/Concise CTCS-552 Slide Rule - Copyright 1966
For Chemical and Mechanical Engineers
Made in Japan by Concise, Designed by Sama & Etani Groton, Massachusettes
Front Scale: 4in || D ( C, CI, L, S Cos, T1 Cot1, T2 Cot2) || 10cm
Back: Table of Elements, atomic weights, Temperature conversions
Insert front: Conversions for Length, Area, Weight, Volume.
Insert back: Conversions for Flow rate, Pressure, Energy, Power, Gas Constants, Velocity.
Company Promo: NUPRO Co. Valves & Filters, Cleveland, Ohio. Texas Valve and Fitting, Irving, Texas
Gift of Arthur Anderson, Boulder, Colorado.
Instruction Manual 4.64MB


Sama & Etani/Concise CTCS-552 Slide Rule (American Oil)

ISRM 12.04.25.02
Sama & Etani/Concise CTCS-552 Slide Rule - Copyright 1966
Recommended for chemical and mechanical engineers and chemists
Made in Japan by Concise, Designed by Sama & Etani Groton, Massachusettes
Front Scale: 4in || D ( C, CI, L, A, K) || 10cm
Back: Table of the Elements
Insert: Conversions for Flow, Pressure, Energy, Power, Volume, Velocity, etc.
Donated By Zdenka Novosad, Louisville, Colorado
Zdenka used this slide rule during her career as a petroleum engineer. She attended high school in Czechoslovakia. She graduated from the University of Pennsylvania (1975) and later became a Petroleum Engineer for Shell Canada Limited and was a member of the Society of Petroleum Engineers. One of her many papers, published in 1996 by the journal 'SPE Reservoir Engineering', was Composition and Phase Changes in Testing and Producing Retrograde Gas Wells and she wrote Spectroscopic and Magnetic Resonance Studies of Aromatic Molecules published by the Graduate School of Arts and Sciences, University of Pennsylvania, 1975.


REF Sama & Etani CTCS-552 Conversion Tables
Sama& Etani CTCS-552 Conversion Tables
Made in Japan by Concise for Sama & Etani, Groton, Massachusettes
Front Scale: 4in || D ( C, CI, L, A, K) || 10cm
Back: Periodic Table of the Elements, Temperature conversion Chart
Insert: Conversions for Flow, Pressure, Energy, Power, Volume, Velocity, etc.
Original Owner: John Vincent Atanasoff, (1903-1995) Father of the First Digital Computer. This scan of one of his three slide rules on display in the ISRM galleries were provided by the Iowa State University Library, Atanasoff Archives. See also his model K&E N4080-3 S/N 798671 for an expanded biography


Sama & Etani 600P Overhead Projector Model

ISRM 11.11.11.01
Sama & Etani (Concise) 600P Overhead Projector Model
Made in Japan by Concise
Front Scale: 4in || D ( C, CI, L, A, S, T, K) || 10cm
Actual size: 2X original = 6 inch x 8-1/2 inch
Transparent Plastic stock and disks
Donated by Carlee Heit in memory of her husband, Ray Heit Collection
Raymond Anthony Heit (1957-2003) earned a Civil Engineering degree from the University of Cincinnati, and was a Registered Civil Engineer in Ohio and Texas and a Licensed Surveyor in Ohio. Raymond had a creative and productive career at Factory Mutual, Inc., Union Carbide, Inc, and Kellog-Brown & Root, Inc. He also collected slide rules and slide charts, which now reside in the ISRM archives.


Sama & Etani Model 600-ST Science Tables and Slide Rule

ISRM 14.01.10.11
Sama & Etani Model 600-ST Science Tables and Slide Rule
Made in Japan by Concise ©1968, Designed by Sama & Etani, Groton, Massachussettes, 01450, USA.
Front Scale: 4in || D ( C, CI, L, A, S, T, K) || 10cm
Note: Scale labels stamped on cursor.
Back: Periodic Table of the Elements, Temperature conversion Chart
Insert - Concise CE ©1968:Conversions for Flow, Pressure, Energy, Power, Volume, Velocity, etc.
Promotional for General Electric. With Manual.
Note: This specimen is slightly warped, but still functional.
Donated by Albert Klumpp, Arlington Heights, Illinos.
Instruction Manual 4.5MB


Sama & Etani Model 600-ST Science Tables and Slide Rule

ISRM 13.04.01.02
Sama & Etani Model 600-ST Science Tables and Slide Rule
Made in Japan by Concise, Designed by Sama & Etani,Copyright 1968
Front Scale: 4in || D ( C, CI, L, A, S, T, K) || 10cm
Back: Periodic Table of the Elements, Temperature conversion Chart
Insert: Conversions for Flow, Pressure, Energy, Power, Volume, Velocity, etc.
Donated by Albert Klumpp, Arlington Heights, Illinos.
Instruction Manual 4.5MB


Concise Science Tables and Slide Rule - US Govt.

ISRM 10.03.01.05
Concise Science Tables and Slide Rule - Copyright 1968
Made in Japan by Concise, Designed by Sama & Etani, Model 600 - Insert ST
Front Scale: 4in || D ( C, CI, L, A, S, T, K) || 10cm
Back: Periodic Table of the Elements, Temperature conversion Chart
Insert: Conversions for Flow, Pressure, Energy, Power, Volume, Velocity, etc.
Advertiser: U.S. Government
Donated by Prof. Robert C. Eaton, Univ of Colorado


REF Concise 600ST Data Computer
Michael O'Leary Memorial
Concise 600ST Data Computer - Michael O'Leary Memorial
Made in Japan by Concise - design by Sama & Etani ©1976
Special run for The International Slide Rule Group
Front Scale: 4in || D ( C, CI, L, A, S, T, K) || 10cm
Back: Periodic Table of the Elements, Temperature conversion Chart
Insert: Conversions for Flow, Pressure, Energy, Power, Volume, Velocity, etc.
Archive - Ted White Collection

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