These tips are the latest in low retention polymer technology and come to an extra fine poin at the dispensing orifice, minimizing inaccuracies caused by surface adhesion and droplet retention. Their universal fit sealing ring design forms a superior seal on a broad range of pipette brands, including hard to fit P20 pipets. The 100uL size are larger and more finely tapered (compared to tradtional tips), allowing them to reach bottoms of 12 x 75mm culture tubes, 0.5ml tubes and even 0.2ml PCR tubes. All sizes are clear and metal free.