The IS process has now universally replaced almost all others. It is not certain whether ‘IS’ denotes its inventors, Ingle and Smith, or its main characteristic which is independent synchronized units with a synchronized gob distribution system to each section (i.e. Individual Section). IS machines can comprise several sections and 10 & 12 section or 16 to 20 section tandem machines are now common.
The machine can operate on the blow and blow or press and blow principle and double gob production, i.e. delivery of two gobs of glass at the same time is common. Triple and quadruple gob machines are also increasingly used. The machine is currently capable of producing more than 600 containers per minute.