VOS laboratory products are top of the line for those who demand accuracy and cleanliness. These high quality stirring rods are made by the leading Dutch medical and research instrument company, VOS Instrumenten.
This stirring rod is made of heat resistant Boro 3.3 glass. Borosilicate glass, unlike plastic, will not retain chemical residue when properly cleaned.
The Brownie Camera Guy says:
In general, I like breaking rules however one die-hard rule in the darkroom is to always keep it clean and uncontaminated. It’s a small thing but these glass stirring rods help eliminate chemical cross-contamination.