High speed gearing from the 60's. Back then the fastest gear ratios were maybe 4:1, not like now when you can buy reels with 8:1 gears and even a little higher than that. This was a bolt-on deal with 3:1 gears inside that multiply the ratio of a given reel X3. In this case it's a Penn 100 Surfmaster with standard 3:1 gearing. With the Reel-Deal trans. it becomes 9:1. It would also fit other Penn's like Squidder's, Jigmaster's and others too. Put it on a standard Jigmaster and you get a 12:1 ratio! Whatever reel it's on, it also becomes a 2 speed reel. Push the knob in and you have stock gearing, pull it out and you get 3X original ratio. I originally got it for tossing iron jigs for West Coast Bonito and Barracuda that like really fast retrieves. It's a little clunky compared to modern high precision stuff but it works and is kinda more fun to use!
I see these every now & then. love to have one to take apart... Jeff
I covered it here for a good look. Dominick http://alantani.com/index.php?topic=18802.0
I have one of these for parts if anyone is interested. Came attached to a Squidder, and seems to be missing the shifting knob and nut.