ANSI station post insulators are one main of post insulator having many types in ANSI standard, such a TR series. ANSI station post insulators are made from porcelain or polymer.

TR series ANSI station post insulators have TR202, TR205, TR208, TR210, TR214, TR216, TR222, TR225, TR227, TR231, TR267, TR278, TR286, TR287, TR288, TR289, TR291, TR295, TR304, TR308, TR312, TR316, TR362, TR324, TR367, TR368, TR369, TR330, TR371, TR372, TR373, TR379, TR391.

In ANSI specification the station post insulator shall refer to a unit or a stack of two or more units.