Full Details

Name and Model Number Lafay Helice a Calcul No. 2
Country of Origin France
Date of Manufacture  
Front Scales 2 spiral
Back Scales  
Scale Length  
Type of Rule Cylinder
Construction Plastic
Area of Use Generic
Rarity RRR
Donor Collection of Rod Lovett
Match Number 20

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.