1963
Electro Products Laboratories
DC Power Supplies
Catalog PS-562R with price list and supplement
Comes form a former missile engineer for the US Air Force.
Was employed under this position during 1950's and 1960's, may have continued on afterwards, all the paperwork I have are from that period.
Superb condition. Well cared for. pages are clean and crisp. Looks like it could have been printed recently not 60 years ago.