This canopy fits the F-4 Pahntom Parkjet.
The model this canopy fits was designed by Steve Shumate along with many of his parkjet designs.
Free plans for his design is on this link.
It is formed with .020 PETG plastic for toughness and light weight.
This piece measures 11 1/4 inchs long, 3 3/8 inchs wide and 2 1/4 inch tall.