This is a mechanical pump seal assembly 5/8 inch, AS-200. It is designed for use on the Pentair SuperMax VS pumps.
Identical to these shaft seals: Advance 6C200, Ampro 6078, AquaFlo 92509020, 92500150, 92500151, Arneson A8, Banker Hydro 35B1178, Doughboy 3061007, Hayward SPX1250Z2, SPX2700SA, Jacuzzi 10000206, 10143600, 100476, PacFab 354545, Speck 60603200, 2920060603, Sta-Rite 173040100, 354545.