HAO just received those sweet photos of MK18 Pony PTW build from Kevin ,the member of Black Thorn Milsim in Canada. With HAO's A7075-T6 Full CNC machined receiver, you aint worry about strength of SYSTEMA OEM one anymore.
Here is the list: Aimpoint PRO Optic
AN/PEQ-15 Surefire Millennium 952V Light Surefire Dual Pressure Switch Daniel Defense MK18 RIS II Rail VLTOR IMOD Stock Magpul RVG Front Grip