Rectangular Refraction Block, 3" (75mm) x 2" (50mm) x 0.5" (12mm) - Optically Worked Glass - Slightly Beveled Edges - Excellent for Physics Experiments & Photography - Eisco Labs industrial_Oct2022 It's very safe even for

It's very safe even for children

never out of fashion

For first use you may need more twisting

Great Fanny Pack - 3 quick easy access pockets and 1 pocket with zipping

Rectangular Refraction Block, 3" (75mm) x 2" (50mm) x 0.5" (12mm) - Optically Worked Glass - Slightly Beveled Edges - Excellent for Physics Experiments & Photography - Eisco Labs industrial_Oct2022 It's very safe even forRectangular Refraction Block, 3" (75mm) x 2" (50mm) x 0. 5" (12mm) Optically Worked Glass Slightly Beveled Edges Excellent for Physics Experiments & Photography Eisco Labs Product Features RECTANGULAR BLOCK Rectangular block made from imported optical glass with optically worked surfaces. All angles accurately worked with edges slightly beveled. Bubble free glass 3" LENGTH Block measures 3" long, 1. 5" wide and is 0. 5" thick PHYSICS EXPERIMENTS