Full Details

Name and Model Number Aristo 948 Universal
Country of Origin Germany
Date of Manufacture 1950
Front Scales cm/ L, A [cos^2, sin.cos, sin.cos, C] D, B, K, BI
Back Scales S, ST, T /ins
Scale Length 25.0 cm + 2.6 cm ext
Type of Rule Slide Rule
Construction Plastic
Area of Use Topography
Rarity RRR
Donor Collection of Rod Lovett
Match Number 5

RR = Rare -- 1 of 25 collectors has one; it may take a year to find an example in the marketplace.   
RRR = Very rare -- only very few known to collectors; may take several years before one comes up for sale.   
RRRR = Extremely rare -- a museum piece; unlikely that an example will ever come up for sale.