Full Details

Name and Model Number Zahl, (A1?) ZAKL
Country of Origin Warsaw, Poland
Date of Manufacture c 1960
Front Scales mm/A/B, C/D/ins.
Back Scales S, ST, T on slide
Scale Length 125 mm
Type of Rule Slide Rule
Construction Plastic
Area of Use Generic
Comment Missing cursor
Rarity RR
Donor Collection of Colin Barnes
Match Number 86

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.