Storage Hook Magnets (4 Pcs. Per Unit) Blue, Yellow, Green and Red. 1 1/2" Diam. Stick these super strong magnets to any magnetic surface to hang classroom supplies, lanyards, pocket charts and more without damaging your surface. The perfect way to keep classrooms, bedrooms and offices organized, these handy and powerful magnetic storage hooks come in blue, yellow, green and red. Metal. (4 pcs. per unit) 1 1/2" diam. Assortment may vary.