TipOne filter tips have a hydrophobic filter made of ultra high-density polyethylene. The filter traps aerosols and airborne contaminants, greatly reducing the risk of sample carry-over and cross contamination. If your sample comes in contact with the filter, it will not be sealed within the tip. You may still dispense the sample for further use. Each hinged rack is individually sealed in plastic and has a tear strip for easy opening without sharp instruments.