Short thread screw seals ND9 are made of PP and are supplied with fitted septa made of a variety of materials. The caps have a 6 mm centre hole and are available in different colours. The screw caps are similar in shape to the crimp caps and are therefore also suitable for robotic handling.

In this case, caps and septa form an inseparable unit (Ultrabond), which means that even a blunt needle is unable to push the septa into the vial.

These septa are temperature-resistant from -40 °C to 110 °C. They are easier to penetrate and have lower particle formation than septa made of natural rubber.