Flux Defense MP17 System: Sig Sauer M17 & P320

You can buy it here https://www.artstation.com/a/23275987
Finally I found the time to finish this project...
“Shoots like a carbine, holsters like a pistol.” That's the pitch behind the new Flux Defense system designed to transform the Army's brand new sidearm into a personal defense weapon.
The Flux Defense MP17 adds a retractable stock, a Picatinny rail, and a second magazine that doubles as a forward grip to the Sig Sauer P320 pistol the Army adopted as the M17/M18 under the service's Modular Handgun System program.