The police at one time carried a leather strap with a few ounces of lead sewn into one end. It was a serious persuader for the ner-do-wells.
Replaced with the ineffective baton. Now the almost useless taser.
Bring back the slap jack!
Where I grew up, they were called "slap jacks". They didn't have wrist straps like this one
https://www.karatemart.com/slap-jack