VWR* Spinbar* Stir Bars, Polygon, Assortment^ 18 PTFE* resin-coated, polygon stir bars contained in a plastic, compartmented Spinbox* with indexed cover. Includes two each of the following: 10x6mm, 15x6mm, 20x7mm, 25x8mm, 30x8mm, 40x8mm, 50x8mm, 60x8mm, a