I first learned about paradiddles from Buddy Emmons. He had a small board with ten short strings attached that he would use for warm up before a show. With this “Speed PiK”, by EZELL & HAWKINS, one could sit anywhere and warm up his or her fingers before actually playing.
Speed PiK
A “paradiddle” could be any alteration of finger motions that would be used for playing a phrase in a tune, especially faster licks. Here’s an example using thumb(T) and second(2) finger: T,T,2,2,T,T,2,2 or T,T,2, T,T,2. It may be impossible to find one of these Speed PiKs nowadays, but if you play steel guitar or banjo using three finger picks, you can use the same types of patterns on your instrument to increase you hot lick speed!
Stringbender
I’m not sure if this manufacturer still exist. I wasn’t able to find them on the internet.