Nope, I'm not needing trench coat advice. Got that already figured out 
Here is a link to a Flashing made by Supervent sold at Menards.
http://www.menards.com/main/heating...-x-6-12-to-12-1-flashing/p-1323296-c-6894.htm
What is the purpose of all those slots around the top??????

Here is a link to a Flashing made by Supervent sold at Menards.
http://www.menards.com/main/heating...-x-6-12-to-12-1-flashing/p-1323296-c-6894.htm
What is the purpose of all those slots around the top??????