Pella sliding glass door, weather stripe on threshold. The door was new in 1994

I am afraid we are having a little difficulty trying to identify your weatherstrip from the photos you sent us. Why don;t we have you start with taking a look at our 58-181 Pella weatherstripping and see if this works for you. If not, send over an additional of the part from and end profile and include measurements. With that information, we can continue to search for other possible alternatives.