Early 70s I would think. You had to be cool to have one of these fine sets. We have the yellow/orange T220 with a Wordpicker highlighter. Then we have the Black T220 ball point with a Wordpicker. Last we have a Scripto Thin Line 49 pencil. These use 0.9mm lead. All these are great items to collect but I think you should open them up and use them. The T220 ball point pen has always been one of my favorite pens and refills are easy to fine. Nothing like using a 40 year pen or pencil. Add them all to your collection.