I believe that is what the red dot was designed to fit specifically, it uses the RMSc Footprint. It fits a few patterns using adaptor plates from either a host pistol or from holosun themselves. I will copy the info from the Holosun site directly for this product:

"The durable housing is made from 7075 Aluminum, uses Holosun’s K footprint, and houses the 1632 battery in a side-mounted tray for easy replacement when needed. The HS407K X2 is a direct for P365X/XL, and requires an adapter plate for slides with a four-boss interface."

Let me know if you have any further questions! Feel free to send a chat message!

I believe I chatted you my phone #. Let me know if you didn't get it