Manufactured according to ISO 3507 standard.
The upper and lower ends of the stopper are ground and excellently polished.
In order to differentiate easily, all density bottles have the same code numbers printed on both the body and the stopper.
Calibrated density bottles are made to contain (In) to 0,001 ml. Net volume capacity is engraved on the body.
Each bottle is calibrated together with its stopper.