Ok, I searched.
One post says: “Most of the time, IQ rubber bands must be from VEX (you can tell by the color)”.
Others repeat the Manual which states " identical in length and thickness to those included in the VEX IQ product line (#32 & #64)". No mention of composition or color.
Several posts mention that VEX uses Alliance brand. One says probably Uline. VEX lists both Latex-Free and Silicone. Alliance shows Non-Latex, but not in #32 size, and no Silicone.
Past Manuals have specifically outlawed HEXBUG rubber bands, but not Next Level.
In the past the Legal Parts Appendix has included: #117B (228-2500-470), #32 (228-2500-474), and #64 (228-2500-475).
#117B is not mentioned in Manuals. Is that from HEXBUG? It is not listed on the Official VEX stores.
Is #117B legal? Sourced from? Documented how?
I realize the Official Q&A is the place, but I am unregistered volunteer working on creating a team. And I know that the Legal Parts Appendix may be here in a month or so, but perhaps the question will still apply.