2 Fel-Pro Inc. Plastic Idus. Gaskets Slide Ruler Promo 1980s NOS New Skokie Il

This has the Fel-Pro logo on it and think they are from the 1970s or 1980s, but not sure of the exact date. This may have been part of a slide rule, as it has a weird T-end on it. Perfect chance to add this neat Novelty Advertising rule to your collection.