Hey , you need a weight belt !
This is what i think is important :
Get a quick release buckle for safety.
I like my rubber belt - doesnt slide around on your suit.
How much weight ?? find what suits you and stay safe!
Some people say a Kg for every mm of suit. but it does depend on how deep you go - you need to find out what your usual depths are and weight yourself adequately.
There are plenty of threads here on weights
good luck!
