kattHi @katt,
I tried these tulip tips out on a knit picks cable. They do fit but the join is not very smooth. Both sets screw on but the way they join is different so the tapering where needles meet cord differ just enough that the yarn catches a bit. I'm working on getting a macro photo so you can really see the difference.
Edit: Here's a photo of these tips on 3 different cords. Knitter's Pride (black), Knit Picks (green), and Tulip (clear).