According to DIN EN ISO 4797, with inscription label.

NS jointed round bottom flasks
Flasks round bottom, NS joint
NS jointed round bottom flasks
Flasks round bottom, NS joint
NS jointed round bottom flasks
Flasks round bottom, NS joint
NS jointed round bottom flasks
Flasks round bottom, NS joint
NS jointed round bottom flasks
Flasks round bottom, NS joint