Three mercury lamps I found a while back, 2X H39KC175/DX and 1X H39KB175.

In this video I run them on a 400W metal halide ballast with a smaller capacitor to reduce the current to safer values. I thought they were 250W intially, turns out they may very well be 175W lamps!

That's why I have another video coming with those three lamps, in which I'll run them on a 175W "yardblaster" light to confirm their actual wattage.