DescriptionRod target for folding rule [product no. 90 2045] made by Keuffel & Esser Co., no date, circa 1960-1965. Round stamped aluminum metal plate, 3" diameter, painted white with round printed decal in red and white with black graduations and lettering; riveted brass fixture on back for clamp screw. Item would typically have been used in surveying field work or building construction for using a lightweight folding rule as a leveling rod. Image is shown of it in use on a K&E heavy duty folding rule; it is a very tight fit which would suggest it was for use on a standard duty style rule. Model number does not appear on object. It appears on page 12-31 of the 43rd edition catalog of 1962. Per donor: source cited that it was in use for over forty-five years which in the year of donation, 2009, would place it in the early 1960s. Note: the decal has text "Pat. Pend." plus "Des. Pat. [Design Patent] 179,838 which was issued in 1957. Keuffel & Esser Co. main office and factories were in Hoboken in the period when this item was made.