The black thing is an oil mist filter. Imo you don't need it. I don't use them, they are not essential. Yea I have the second pump, the blue one. The more the cfm, the faster the pump will pull a vacuum. The micron rating of the pump is how deep the vacuum pulls. You will be much happier getting the robin air. The only fittings you will need is the kf25 to 3/8 bard hose adaptor flange from AI, a 1/4" silicone vacuum line (amazon), and a couple brass fittings for the pump to get it to hook up with the vacuum line.
I suggest you use vacuum grease and hose clamps on the connections for the silicone vacuum line to make a good seal and pipe tape on all the brass fittings.
If you have any more questions feel free to ask bro. Good luck