Our number one choice among knee pads is the DEWALT DG5204 Professional Knee Pads. We have found them to be the best knee pads for kneeling on hard surfaces for extended periods of time.
We are impressed with the way DEWALT professional knee pads are built. They are very durable and built to last. They have a layered gel on thick foam padding that provides an incredible amount of cushioning and knee comfort. The gel is then covered with a solid, non-slip material designed for use on all types of surfaces. These knee pads cover you no matter what type of floor you are working on.
These knee pads have sliding buckle straps that keep them over your knees. However, they are not tight, so they tend to move while you work. When they do, the straps are very easy to adjust to snap them back into place. They have a neoprene lining that gives them the right balance between the firmness they need to resist the ground and the softness they need for maximum comfort.
Advantage
Durable
Easy to adjust straps
Neoprene fabric lining
Gel-covered foam cushion.
Balance firmness / smoothness
Anti-slip
Good for multiple surfaces.
The drawbacks
Not tight
The straps are stored behind the knee.
More Info : https://uscsc.org/best-knee-pads-2019/