Guitar straps and wrist band

Hello Ladies,

I have noticed in your fantastic videos that Mona always has on a MonaLisa Twins guitar strap. Whereas Lisa has a plain tan one on. Any particular reason. I thought you both would have an MLT one on .

Also, Lisa always has what looks like a hair tie on her right wrist. Is that in case she needs to pull it back. Its in almost all videos of you. Or perhaps superstition. Thanks