Filter holder for Olympus BH2

So my particular model of BH2 is equipped with the BH2-SC swing-out condenser which we love for wide views on the 2x and 4x objectives, but we still wanted to have at least some sort of darkfield capability without changing or modifying the condenser.

The filter holder clicks into place just under the condenser dovetail, on top of the metal tabs and accepts a sled with a small detent to lock it in place

Despite being approximately 30mm below the condenser diaphragm, which isn't really ideal if we're being honest, it still manages a fairly dark background even with a 40x objective