This vintage NOS Sanford VIS-a-VIS Overhead Projector Pens markers are a rare find, coming in a full box of 12. Made in the USA by Sanford Corp, these pens are specifically designed for use on overhead projectors. The vintage aspect adds to the collectible value of this set, making it a unique addition to any collection of pens and writing instruments. Check my other listings for different color vintage Sanford Vis-a-Vis pens
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