I'm with Grainraiser on using duo-lock snaps, rather than speed clips. I don't remember what "size" they are, but I do know they're the 20# test strength. I've always used them for casting cranks (for Bass) and on the main lines of my 14' Pushing rods. I have pre-rigged leaders w/jig heads tied on one end & a loop knot on the other end of the leader, so I can switch out quickly if I ever break off or want to change baits.

I think I bought a pack of speed clips a long time ago, but don't remember ever using any of them ... though I think I may still have ONE in one of my tackle boxes (hook/sinker box), but I have no idea what happened to the others of that pack.