Hello everyone. Here's what I know about the blue reel at least: The tape formula for the reel I had was "311 Tenzar". It was a black and gold box and had a piece of blue tape on one side of the box, I'm guessing to show the reel color. The look of the tape was also quite interesting as it had closer to a red color/off brown to it, and the edges of the tape almost appeared like a bright metallic pink if you were looking at the tape on the reel or on the machine. The only blue 7" reel I've seen was the one I had. However, I'd run across at least two 5" reels with tape in their boxes in a media room at.a school I went to in the 70s. I've been looking for one of those blue reels to replace the one I had which was stolen from a storage unit, so if anyone has an extra one they'd like to sell... Also, I searched "Scotch 311 Tenzar" and found an ad in Billboard magazine from 1960 advertising the new tape. I've never seen that design in red or yellow until I saw the pictures in this thread, but I could have sworn I saw this design in a smoke color on a machine in a hi-fi store several years ago. It was gone when I returned to ask about it. I've seen the next design of this reel in red, yellow, blue, and smoke color. It was probably made sometime in the 70s with the larger script. I'll upload a picture as I found a blue reel with that design.