Charlie Bates Diffraction Grating Peepholes™ - Fun with Diffraction Gratings!! Preprinted Charlie Bates Diffraction Grating Peepholes™. Always in stock and ready to ship. The ideal teacher incentive. Great in the classroom when a quality diffraction grating is needed for the study of Light and Color. Just look through your Rainbow Peephole at any light source...the rainbow starbursts will amaze you! RAINBOW PEEPHOLES: 13,500 Line/Inch Diffraction Grating - 1 11/16" Diameter, 1/2" Window - Heavy Carboard.

IMPORTANT: Minimum order for this item is 100 pieces at .30 each. To recieve the quantity discounts advertised, you must add the quantity you're ordering to the quantity box on the order page.