Specs : 320mH / 600mA / 10 ohms . This part was recommended by Jeff Medwin aka Drlowmu for use in LSES filters in the L1 & L2 position. He thought that this part would have similar performance attributes to the Stancor C-2708 filter chokes that Dennis Fraker apparently uses in his Serious Stereo SE DC 2A3 amplifiers. I thought that this suggestion was reasonable and purchased (6) units for low DCR filter experiments. I found the C-40X to have a mechanical buzz at low currents (60-65mA) in a SE RC 6AQ5 stereo circuit, so I can't personally recommend this part for L1 duties.
I have used the Triad C-40X in the L2 & L3 position in various low DCR filter circuits with some success.
The Stancor C-2708 has the same specs as the Triad C-40X, but is reported not to suffer from mechanical buzzing issues when used in the L1 position in LSES filters at low-moderate DC currents. I have not personally used this part or know if current production Stancor C-2708 chokes deliver the same performance as the older production models.