Pulls on Tape: The Elves in the warehouse put the pulls on the tape for you. $1.20 per pull which includes labor & the pull.
Pulls NOT on Tape: YOU put the pulls on to make the zipper tape open & close.
I have been testing this weight of invisible zippers in cushions and in the backs of slipcovers for years. Invisible Zippers are NEVER as strong as a standard coil zipper! To take the stress off the zipper when closing, I make sure that I pull the zipper tape together prior to trying to zip it up or sit on the cushion as you close the zipper!