Brake pipe flaring

[flyerncle]

Convex on male fittings, operation 1,concave on female fitings, operation 2.
Easiest way to tell is look inside the hole you are putting the pipe into and most will have convex flare. If you are using copper brake pipe it will nearly flare itself but be carefull its you life and others at the end of the day and make sure you have no leaks under pressure.