Ideal for your serological pipettes from 0.1 to 50 ml. Click together horizontally or vertically to build the desired configuration. Magnets on both sides of the units connect securely and safely to most metal surfaces of cabinets, freezers, refrigerators and fume hoods. Protective lid encloses the unit to prevent dust build up and provides additional shelf space. 3 assorted shades of blue. Ideal for your serological pipettes from 0.1 to 50 ml. Click together horizontally or vertically to build the desired configuration. Magnets on both sides of the units connect securely and safely to most metal surfaces of cabinets, freezers, refrigerators and fume hoods. Protective lid encloses the unit to prevent dust build up and provides additional shelf space. 3 assorted shades of blue.