Replacement Window Materials: 5 Benefits of Ultrex Fiberglass

  Infinity from Marvin fiberglass windows and doors are made with Ultrex® fiberglass, making Infinity windows more durable than vinyl windows and needing less maintenance than wood windows.   5 Benefits of Ultrex Fiberglass More view for the money Because Ultrex is so strong, we actually use less of it in Infinity window frames. That …