Constricted NMR tubes offer a convenient way to seal your sample from air or other contaminants. To seal, simply heat the constricted portion using a suitable heat source (e.g., a small butane torch), then gently twist and pull the open end to create a permanent seal. This design also allows samples to be stored under vacuum or inert gas atmospheres.
Please note: Constricted tubes are specified and ordered by their required finished length (measured from the tube bottom to the center of the constriction), as shown in the table below.
3mm - 10mm
1.2 ± 0.05