Local inventor Tom Kahan sold a bunch of these Flecto Spinners in the previous decade around the Bay Area. He’s making these Made-In-California reflective spinners available again through this crowd funding campaign at Indigogo.
As Tom notes in the video, Flecto Spinner can also be used on scooters, wheelchairs, and strollers. The tubular clamp seems particularly clever to me.
The fund raising begins February 22. More info at Indiegogo.com: Making Cycling Safer Plus More Fun for Everyone!> Tom also has a product website that tells his personal story.