These stand-alone knee guards feature a hard molded knee cup and two hard plastic wings to protect the vulnerable sides of the knee. They are secured via elastic Velcro strapping and an elastic tie meant to attach directly to the loops on your fighting pants. (Keep an eye out for our very own pants from Superior Fencing designed to work with these knee guards.)
Simple knees with side protection can be hard to come by. These also have cushioning on the inside, and ties up top to attach to different HEMA pants. While there are full legs on the market that have the "wings" on the sides to protect the back of the knee, these are one of the only knee protectors I've seen that offer those as well. We keep them at the club for anyone that wants to use separate shin guards.