Preparing a Schlenk tube

We need the following materials for the preparation of a Shlenk tube:

- Schlenk tube
- Stop cock
- Cap of schlent tube
- Some vaseline
- Two elastic bands

The first step is to put some vaseline in the stop cock, so that when we insert it in the schlenk tube it moves easily.
Now, hold the schlenk tube with your left hand and make sure the stop cock is perpendicular to you. With the right hand,  hold the elastic band down the stop cock and pass it straight over the top of it. Next, twist it once, and go back over and twist it again, go back over and finally go the way down; This way, we assure that the stop cock does not come out.

In the last step to prepare the schlenk tube we need to put the cap on its corresponding place. With the second elastic band; we double the elastic band and put it over one metal hook and pass it underneath and then put it over the opposite metal hook.

Now, the schlenk tube is ready to be used.