Usually the things they display in parades are vapour ware, but on occasion they might be the next stage for transporting the nuclear bombs they’re developing on a parallel track.
[IsraelTimes] The head of Iran’s Islamic Revolutionary Guards Corps air force says it will soon unveil a newly developed "strategic missile," Iranian media report.Amir Ali Hajizadeh says that the missile has been in production for a while and is already being used in combat operations.
No other details are available.
Iran
...They hate recently carried out a drill in which it showed off new ballistic and precision-strike cruise missiles, calling it a threat aimed at Israel.