How Effective is this?

There have been no reported bitings from sharks with a shark bell attached.

So pretty damn effective.

Isn't it dangerous to bell a shark?

You bet your sweet ass it is. But belling sharks is not only a great rush it is also a way to help those wankers who can't protect themselves. We've all seen them on their SUPs or wading in the whitewash. Poor fools would be bait without us.

How do I know which shark bell to purchase?

Shark Bells come in a range of sizes to accommodate the different size shark species. So if you are a scared wanker who swims will small sharks get the small ones. If you are a badd ass and swim with the tiger sharks and Great Whites than go big. 

How much warning do the bells give?

Scientifically speaking, sound travels about four times faster and farther in water than it does in air. So if our medium shark bells are audible from 75 meters than that is 300 meters in the water.  The average shark swims at 10 meters a second which gives you 30 seconds to get your ass out of the water.  The bigger the bell the more warning you get.