Halogen ballasted mercury lamp

Here is a lamp claiming to be a self ballasted metal halide lamp. However, seemingly no halide salts are in the arc tube, making it a pure mercury discharge. What's also unusual is that the lamp uses a halogen capsule to ballast the arc tube instead of a standard open filament. It's typical Chinese quality, but quirky enough for me to want to give them a go. It looks like a 400w halogen lamp with a 125w mercury tube.