It is possible to pass down 5 IVs to the offspring if a perfect IV parent is holding a destiny knot. Another parent with a specific stat with perfect IVs can hold an EV growth item (e.g. a Power Weight to pass down HP IVs, a Power Bracer to pass down Attack IVs, etc.) can pass down IVs in one particular stat to the offspring. If you're lucky enough, the parent with the destiny knot will pass down perfect IVs in every stat except the stat that the other parent is passing perfect IVs to.
If you're new to IV breeding, I recommend this video.