These are VINTAGE LEFAX BOOKS~ General Chemistry, Machine Design, General Mathematics, Heterogenous Math
LOT OF 4

VINTAGE 1940s
A pocket-size system of loose-leaf data sheets and blank forms for keeping facts at your fingertips. 
Individual pages may be reprints as early as February 1948.
Publisher: LEFAX, Philadelphia, Pennsylvania


NO 606, 613, 629, 647

Very good condition

I inherited this from a family member. 

It has been kept in a dry, clean, smoke free home and very well cared for.

Let me know if you want me to combine shipping.

Please ask questions if need be.