3M - Remember the overhead projector? It inspired a way to help make our roads safer. In 1962, 3M's Roger Appeldorn and his team created an overhead projector using a new, lighter
3M 1615 OHP
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Lighting-Gallery.net - My Own Light Fixtures/3M Overhead Projector 9100
3M 1610 Overhead Projector HK 4000-0036-8 B&H Photo Video