I have the exact same capper. I'm in Toronto - are you as well? And by chance did you buy it from "Toronto Brewing Supplies" up near Danforth station?
Not 100% sure that it'll work fine with screw cap type bottles, but I'd say yes. One way to test would be to cap an empty bottle and submerge it under water, if you see bubbles then there's a problem.
...and I don't know what it's called or who makes it. Call whoever sold it to you and they know (assuming you didn't buy it second hand).