Table:
|  | 2019 | 2018 |
| --- | --- | --- |
| Prepaid services | $221 | $252 |
| Prepaid bonds for German statutory costs | 188 | 199 |
| Prepaid insurance | 62 | 19 |
| Prepaid licenses, software tools and support | 17 | 51 |
| Other prepaid expenses | 17 | 17 |
|  | $505 | $538 |
Paragraphs:
4. PREPAID EXPENSES
Prepaid expenses consisted of the following at December 31, 2019 and 2018 (in thousands):  Prepaid expenses consisted of the following at December 31, 2019 and 2018 (in thousands):  Prepaid expenses consisted of the following at December 31, 2019 and 2018 (in thousands):
In 2018, we recorded impairment charges of approximately$0.4 million related to prepaid licenses and production tooling as a result of the restructuring of our operations. These charges are included in “Restructuring expenses” in the accompanying statements of comprehensive loss (see Note 15).
Question:
What is the content of Note 4 about?