Features:

Made of steel 

M18x1 threads, compatible with big-bore Ronin, Emperor and Great Kami moderators with M18x1 endcaps

Comes with a black anodized Aluminum thread protector

Adapters are meant to be a tight fit and have two set screws (M4) to help secure to the barrel

In some cases, proper installation may require sanding inside the adapter

Uses 2mm hex keys for set screws