knee pads

Hi All. I've had a quick search and I see this has come up before, but not for a few years, as far as I can see? I was just wondering if anyone had any recommendations for knee pads, please? I've used various cheap ones, and they're "OK" but after a while, always seem to slide down my leg, or...

Having recently had an op. on my knee and it's still quite sore I'd like to get some strap on knee pads. The single strap ones are definitely out as I think they would slip and move easily. A wider two strap product would appear much better. The Redbacks look very effective but they look quite...