Re-gripping or grip transition is super important during the snatch. Re-gripping is what keeps your hands from ripping and avoiding blisters.
As you snatch the kettlebell up the grip transitions from hook grip into the loose grip. You punch into the corner to obtain that 45-degree angle which is so important to avoid the broken wrist grip.
All these things and so much more are explained in our online kettlebell snatch certification and book. Of course, if you have not mastered the basics, the fundamentals of kettlebell training, you should look at that first as otherwise, you’d be building upon something that will come crumbling down.
Remaining in extension on the drop from overhead is important to prevent lower back pain. Following the kettlebell is a big issue with the kettlebell clean, swing, and snatch that can mean the difference between no back pain or being out of action for a while. Check out the book Preventing Kettlebell Training Injuries by Cavemantraining to understand and prevent all the common kettlebell mistakes.