Back pain, sore hips, carrying too much lead... a harness can help with all these issues. The harness sits higher on the body allowing you to carry the lead like a backpack which takes all the stress away from your lower back and hips. Duck-diving will be easier as the weight is over the more buoyant chest area and is more forward of your center of balance.
In the design phase of making this harness, there were a few issues that needed to be addressed....
First and foremost was safety. Can you get your harness off quickly if you have to? The short answer is yes. On both shoulders straps, there is a quick-release buckle which when squeezed will also release quickly and efficiently.
The second main point is cost. Replacing your weight system can run into the hundreds, but the robust pocket-style weight holders can easily fit your old 1.5kg buckle weights.
A great spearo alternative weight - system for many spearos there is the ability to hold 6x 1.5kg weights.
An ideal combination is to split your weights over a belt and a harness, 3kg on your belt, and the balance in your harness. This we have found will give you the perfect combination and allow you to lay flat in the water.