VINTAGE 1971 FABER-CASTELL SLIDE RULER RIETZ MODEL NO57/87 MADE IN GERMANY

The FABER-CASTELL SLIDERULER WAS THE SECRET WEAPON FOR SCIENTISTS TO DO CALCULATION IN THE MID 20^THCENTURY. The Faber-Castell slide rules were some ofthe most elegant and well designed slide rules ever produced.
THIS ONE WAS MADE INGERMANY WITH BATCH NUMBER 971 WHICH INDICATES ITS MADE IN SEPTEMBER 1971.
The box says :A.W. FABER-CASTELL STEIN BEI NORNBERG GERMANY. 
IT ALLOWS FOR MULTIPLICATION, DIVISION, SQUARING AND SQUARE ROOT OF NUMBERS.
INFO / SCALES
This ruler from Faber-Castell features their unique trademark "mint-green" accent stripes on the slide and body to align the A+B and C+D scales. The CI (reciprocal) scale marks are in red.
This rules has (Sin and Cosine), T (Tan and Cotangent), ST (arcsin or small angles) scales on the reverse.
All in all it features 9 Scales. Front K Cube scale), A, [ B, CI, C ] D, L (common logarithms) Back - [ S, ST, T ] + Equiv. chart
Size 32CM WIDE IN BOX
CONDITION: GOOD VINTAGE CONDITION. HAS THE ORIGINAL INSTRUCTION BOOKLET. PLASTIC CURSOR HOWEVER IS MISSING BUT ALL THE CALCULATIONS CAN BE DONE WITHOUT IT - IT IS ONLY THE CONVERSION OF UNITS THAT CANNOT.
ALSO SEE MY OTHER ITEMS LISTED.