Screw seals ND15 are made of PP and are supplied without or with fitted septa made of a variety of materials. They have a 15-425 thread, a 9 mm centre hole or are closed.

Screw seals ND18 are made of PP and are supplied with or without fitted septa made of a variety of materials. They have a 18-400 thread, a 12 mm centre hole or are closed.

ND15 seals are suitable for items 7.616 898, 7.618 935, 7.616 655 and 7.618 936.
ND18 seals are suitable for items 7.616 899 and 7.616 139.

These ND18 screw caps with 18-400 thread are not compatible with ND18 precision thread vials !

These septa are temperature-resistant from -60 °C to 200 °C and have better purity than septa made of natural rubber or red rubber. However, they have less effective resealability properties and are therefore more suitable for single-injection applications.