So...First- it came without the screw and catch showen on the picture! This missing parts are needed to fix the upper part firmly so it dosent wooble...The screw hole is displaced. It's on the front of the upper part, while it should be on the rear, so it can bi fixed to the delta ring.The build quality is ok, finish too. It is metal/potmetal made. It's JG__ Golden Eagel.
With minor modes it fits JG M4 GBBR. I rated it with 3, because of the missing parts and manufacturing failiur....