The iPhone Guru discovered that the bracelets fit perfectly around the body of the iPhone 4. After using a pair of scissors to cut holes for the dock connector, the silent mode toggle, and the headphone jack, the band was slipped onto the phone and ready to go. The iPhone Guru reports that reception is "much improved" with the band in place.
At 10 for $10, they're much cheaper than Apple's Bumpers, and your purchase supports cancer research to boot. Of course, any instance of this type of rubber wristband will probably work. Alternatively, check out these decals on Etsy -- three 3-packs for $9!
Live strong, iPhone 4. Live strong!
Thanks to everyone who sent this in