Recovery Strap - Where do I start?

Title of the thread says it all! So I'm interested in getting the gear required to be safe and prepared while off-roading. I want to buy a recovery strap but have no idea where to start. Any advice? What is necessary and what is overkill? Good brands? Any good videos that explain how to use them safely? Should I be buying the shackles? I have a Big Bend would the recovery strap be used differently with those recovery points versus the ones on say a BL or BD?

Thanks!
Ted