The TT T ET post Insulators for medium voltage: 35 and 20 kV. Here the most Deltas was changed to this type Insulators with steel-aluminium cup, they are unipart.

The most generan Insulator for strain, the suspensions didn't win unfortunately, the rods won. The suspension strain is rare.

The older type rod for strain.

This is a FIDENZA Italyian 3 part Insulator, some providers use this like Insulators in North Hungary on 20 kV, the straining are the brown porcelain rods. Some providers use epoxy plastic Insulators :-(