Does anyone know if that blast shield fits the pinned and welded flash hidder on the DDM4A1 RIII?

Unless you have their comp on the end of your barrel, it won’t work. You have to have there’s. Hope that made sense..

I might be eating my words.. The locking mechanism might partially engage on the DD comp/FH, but might not all the way engage, if that makes sense. Give Griffin Armament a call to confirm, great customer support!

It is designed to attach to a standard A2 flash hider. I like to use it with griffin muzzle devices because they all come with an over travel stop washer. On an A2, without the washer, you kind of have to "search" a little to get it locked.

If the DD device has the same profile as an A2 it will work. I would recommend getting the washer, it makes it faster to get the blast can or suppressor on. (ETA: Missed the OP'S p&w part. Haha. No washer.)

Pics of stop washer: