Rubber. For removing heavy soiling from test tubes by scraping. With 5mm boring for rod. In various styles as indicated below.
Brushes for test tubes
Test tubes brushes
Test tubes cleaner
Brushes for test tubes
Test tubes brushes
Test tubes cleaner
Brushes for test tubes
Test tubes brushes
Test tubes cleaner
Brushes for test tubes
Test tubes brushes
Test tubes cleaner
Brushes for test tubes
Test tubes brushes
Test tubes cleaner