These are genuine US military surplus Knee Pads (a set of 2) in Multicam / OCP camo. They are designed for the to sit over top of the knee and secured in place with the two elastic Velcro straps.
These knee pads are made by various manufacturers and military contractors, and may have slight visual differences.
These knee pads have been previously used and issued by the US military and most are in very good condition. They will show minor signs typical of use including some dirt and scratches.