Combined slide rule/slide chart specially commissioned by Japanese engineering company Chiyoda + conversion factors on back + removable data card with weight, length, square (area) & cubic/capacity conversion tables 

Combined slide rule/slide chart designed by SAMA & ETANI & specially commissioned by American engineering company Brown & Root Inc. + reactance nomogram on back + removable data card with length, weight, area, volume, energy power & velocity conversion tables - EE model name prefix = Engineering & Electronic

Cadillac Publishing Co. with give-away unmarked “10-B” with vol.1 of their Self-Teaching Encyclopaedia

Conversion Tables on back

Conversion Tables on back

Conversion Tables on back

Conversion Tables on back

WINSCO Wabash Instruments & Specialities Inc. on back + - Tables of Constants 

Conversion tables on back

Identical to ver. 1 but promoted in different colour box + Conversion Tables on back 

Specially commissioned by Lakeside Toys +  DRAFT-A-PLAN BY LAKESIDE printed on rule

Unmarked “5-B”

OEM rule made by American maker ACU-Math (model 150) - unusual layout means the back is often mistaken for the front

OEM collaboration between Lakeside & Engineering Instruments

Monchrome blue version of standard 10-B with conversion tables on back

How To Use It (instructions & tests) dirty orange & black book by Sommers/Drell/Wallschlaeger & published by Grosset & Dunlap 

How To Use It (instructions & tests) dark-green & gold book by Sommers/Drell/Wallschlaeger & published by Wilcox and Follett Co. with extra loose-leaf Answers addendum + slide rule in back

Early & famous 25¢ slide rule - read more ….

Conversion tables on back

For area % up & down scaling

For lumber volume in board feet

For lumber volume in board feet

For discount or profit margin mark-up per gross/dozen/each in $‘s

For recommended machining cutting speed in f.p.m for given drill speed & size

For calculating the scaled down dimensions (various railway gauge sizes) for replica scaled models of railroads/trains

For moving between inches & picas when printing/publishing

For font size and letter/word/line spacing in points and picas - layout © Owen T. Taylor

For calculating days between two dates & pro-rata premium/days

Conversion tables on back

Conversion & gauge marks tables on back

Conversion tables on back

Conversion tables on back

Marketed as a “Professional Slide Rule” - conversion tables on back

For Photoflash Lamps but missing top colour film scale found on the later Flashrule version  - photography tips printed on back​

For GE or Westinghouse Photoflash Lamps - photography tips printed on back

For WABASH Photoflash Lamps - photography tips printed on back

Conversion table printed on back - Wabash made

Conversion table printed on back - Wabash made

Paper table of decimal equivalents on back

For minimum wire size/volt (440/220/110) in A.W.G. - conversion tables on back

For constructing chords in any key & transposing one key to any other

Specially commissioned by B.F. Grizzle for calculating gas rates through displacement meters @ various pressures - layout © B.F. Grizzle

Specially commissioned by B.F. Grizzle for calculating open flow rates using pilot tube pressure readings - layout © B.F. Grizzle based on Spitzglass’ formula

Specially commissioned by B.F. Grizzle for calculating the gas flow capacity/hour through a pipe of a given diameter - layout © B.F. Grizzle based on Panhandle Eastern Pipe Line formula
 

Specially commissioned by B.F. Grizzle for calculating the friction loss in a section of water pipe & head loss for a given pipe diameter, length & flow - layout © B.F. Grizzle based on Hazen–Williams equation

Specially commissioned by B.F. Grizzle for calculating open flow rates based on pilot tube pressure readings & using Reid’s formula for pipe profiles - layout © B.F. Grizzle

Specially commissioned by B.F. Grizzle for calculating the size of conduit restriction needed to create a required pressure drop - layout © B.F. Grizzle

Specially commissioned by Canadian Radium & Uranium Corp. for commercial (steel or alloys) rather than medical use - for determining the appropriate exposure times for radiographic images involving radium-226 sources

Specially commissioned by Caprock Materials Co. for calculating cubic yards of concrete needed for or in a wall of certain dimensions

Part of loyalty scheme for sales of WHIZ chocolate bars

Rules carry an advertisement for Robin Company, Chicago

Because of the Dick Tracy connection presumably marketed in cooperation with the “Chicago Tribune New York News Syndicate”

Specially commissioned by Fun Incorporated + © design from 1950 by Ideas Unlimited read more …

Specially commissioned by L.E. Waddington for adjusting relative vibration rates, degrees of scale, intervals, chord structures, scale indications & transposition data against a piano keyboard - based on several standard frequency level specifications - layout © L.E. Waddington - Reference Frequency table in well - Subscript Notation, Instrument tables, Time Signatures & nomograms on back

Specially commissioned by Madison Manufacturing Company for calculating the drill and cutting speed for machining a given diameter - extra tables on back

Specially commissioned by Miller Motor Company for calculating air & hydraulic cylinder values such such as thrusts, bores, areas displacements, etc - conversion tables on back

Specially commissioned by Murphy & Murphy Inc. for calculating cubic yards of concrete needed for or in a wall of certain dimensions

Specially commissioned by Pioneer to calculate approximate 'Grade A,' 'Grade B' & 'Principal City' Coverage for all VHF and UHF Television Stations from TV station's published power & antenna height + gives approximate field strength in microvolts/meter for distances up to 100 miles from transmitter + UV/M-DB conversion scale on back - layout © J.B. Epperson

Specially commissioned by Plaza Express Company Inc. for checking freight shipping charges or shipping rates or shipping truck/carload breaking points & calculating storage costs - layout © M.T. Brockman

Specially commissioned by Radio Corporation of America for estimating coverage of FM radio stations according to the type of RCA antennae

Specially commissioned by Statham Laboratories + © design from 1950 by Ideas Unlimited read more …

Specially commissioned by Taylor Publishing Co. with scale layout © Owen T. Taylor & identical to 12-H + CCP paper table gives Characters Per Pica for extensive list of different type faces & fonts for both upper & lower case - 

Specially commissioned by Tenbrook Enterprises for calculating the temperature correction (°F) needed when making bulk deliveries of Propane

Specially commissioned by Thomas Specialities for composing, transposing or creating harmonies - layout © Thomas

Specialty commissioned by Tokheim Oil Tank & Pump Corp. for calculating supply requirements of household heating/fuel oil - K factor is a way of showing (gallons/degree day) how fast a consumer uses fuel (analogy = miles/gallon in a car)

Specially commissioned by US ARMY + called a “Graphic Table” by the US military & used for “Bracketing” i.e. flooding an area with shells rather than precise aiming - “Y” probably refers to Howitzer gun & “OE” = observed errors + Mils range suggests mortar shelling

Specially commissioned by United States Aviation Underwriters Inc. for actuarial-based calculations + table on back for cancellation ratio’s/days - layout © Albert J. Smith