20-piece assortment of stir bars, made from high-quality magnets coated with PTFE. Set includes: * 2 octagon-shaped stir bars with pivot ring, 15mm x 7.5mm * 2 octagon-shaped stir bars with pivot ring, 25mm x 8mm * 2 octagon-shaped stir bars with pivot ring, 35mm x 9mm * 2 octagon-shaped stir bars with pivot ring, 40mm x 8mm * 2 octagon-shaped stir bars with pivot ring, 48.5mm x 10mm * 2 polygon-shaped stir bars without pivot ring, 12mm x 3mm * 2 polygon-shaped stir bars without pivot ring, 70mm x 9mm * 2 egg-shaped stir bars with blunt edges, 15mm x 7mm * 2 egg-shaped stir bars with blunt edges, 30mm x 13mm * 2 egg-shaped stir bars with blunt edges, 50mm x 20mm