I ran across this antenna on Ebay yesterday and it caught my eye thinking a simple modification would make it suitable for a dual band VHF/UHF air-band antenna for scanners. However wouldn't the dipole elements conflict with each other being so close together? In any event it's interesting to note it was fabricated using 3D printing.
Mast Mount & 2m / 70cm Vertical Dipole Antenna. Antenna, horizontal stand off, Mast and Vertical mounts included! No Antenna Required for out of box tune. (144.0-148.0 mHz (2m), 420.0-450 mHz (70cm)).