Will this unit work for a MMC cap?

I just found a capacitor in the Fair Radio catalog that looks like it
might be suitable for a MMC system. It's listed as a filter cap, 100
nF/3.5 kV, manufactured by Sprague. They cost $2.50 each. It says
"SPRAGUE JX FILTER CAP", so JX is presumably the series code. To those
out there who know about these things: will this work in a tesla system?
(I can limit my run times if necessary--I don't plan on anything longer
than a minute.)

Also, a question about a post a while ago: what is a snubber capacitor?
Some units from Hosfelt Electronics were described that way.

                --Doug Brunner