Review on Powertec 70175 Dust Collection Hose: Efficient Fittings, Two Reducers & Black Color by Steve Snyder

I'm an amateur at this dust collecting game. I thought people had standard power tool fittings and whatnot, but that doesn't seem to be the case. So mostly these things don't fit - one of the 6 options (loose ends can be flipped), most fit my tools and then I have to stack them on top of each other and it loses pressure etc etc. So do yourself a HUGE favor by doing FIRST measure all your fittings. and measure ID and OD (inner diameter, outer diameter). If you see something that matches "4" it doesn't mean it will fit YOUR tool if you have a 4" ID and it also has a 4" ID. One of them has to be 4" OD for them to fit etc. They are very unclear in the description and now I have a bunch of confusing details.