I picked up an excellent condition but slightly used Walther P22 yesterday. Threaded barrel, and I thought I could place my adaptor I’ve used on previous pistols. After finding out my adapter won’t work, I found out that there are 2 different adaptors to be used. They have them on their website as well. My question is: how do I tell which adapter to buy and use on the pistol? Does it go off of the weapon SN, or what? It’s a bit confusing for this old fart, and any help is much appreciated. The suppressor I have is a Tactical Innovations and I use it on a Ruger 10-22 as well. Thanks in advance!