There are three versions of the MCX Virtus.
Unless you know what version you have, you will have to check the threading on the barrel of your airgun.
The Gen 1 MCX works with our MPX adapter, and it has 3/8x16 thread.
https://donnyfl.com/products/mcx-virtus-1-2-x-20-adapter-a76?_pos=1&_sid=902845773&_ss=r&variant=40848346120235
The Gen 1.5 MCX has M11x.75 thread, and we can make a custom adapter using our MCX adapter.
The Gen 2 MCX has 1/2x28 thread and you will need to buy a firearms silencer and go through the tax stamp process.