Here are some 120FPS slow motion spin serves of Porter Barr who I believe currently has the best one handed spin serve in the game. Unfortunately we didn't have a lot of time to film all the different variations, but this should cover a good amount of what Porter does during his spin serves.
His paddle the Selkirk Amped Epic: https://bit.ly/3ujIquY
My Instagram: https://bit.ly/3GO6s5O