Therma-Tru Astragal Bolt for 7/8 inch T-Astragal.
The bolt goes at the top and bottom of astragal, moves up and down to lock or unlock passive door.
Available in 2 lengths: Short 2-5/8 or Long 17 inch 

NEW Style: 7/8" wide
Overall Length: 4"
Bolt Length: 2-1/4"
Width: 13/16"
Thickness: 7/16"
Track Width: 3/8"
Material: Plastic
Color: White

Old Style: 5/8" Wide
Length: 
Width: 
Thickness: 
Material: Plastic
Color: White

New Style will not fit old 5/8 astragals - Not interchangeable