“U” is for the Univex Uniflash. The Universal Camera Corporation made several really neat plastic cameras. The Uniflash is among my favorites.
The Uniflash was a simple plastic viewfinder camera that had flash synchronization. This meant that the flash would pop when you tripped the shutter.
It was a cheap camera, however. Notice that the iris in the lens is actually just a metal diaphragm etched to look like an adjustable iris.
Reference: McKeown’s Price Guide to Antique and Classic Cameras, 12th edition, ISBN 0-931838-40-1
The other cameras featured in this A to Z Challenge are linked on this page.