I personally use asicis 09 volleyball knee pad I play a lot and they last me awhile but downside they do tend to slide.
These are the ones I got. I usually shop around for Volleyball or Wrestling tailored knee pads since I'm a little bigger.
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https://www.amazon.com/ASICS-ZD0009-P-Asics-Knee-Pad/dp/B001ANV9EC?th=1&psc=1