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Here is my pick of the best for hand technique. IMO best money you could spend to improve your playing.

It's called "Secret weapons for the modern drummer", a hand guide to technique.

JoJo Mayer presents this guide of not so modern but proven over time techniques for drummers of all skill levels.
Very good explanations and interesting detail on grip and other concepts.
I got my copy from EBay, it's a Hudson Limited DVD and very good value at 3 hours running time, an invaluable and cheap lesson.

Only fault with this is, it wasn't available 20 years ago.

No serious drummer should be without a copy.