BioWave BioWrap Knee Electrode Compression Wrap for Pain Relief Device, Large/Extra LargeACCESSORY ITEM FOR USE WITH BIOWAVE GO (sold separately) BioWraps deliver direct and deep therapy when severe pain strikes for up to 24 hours after one 30 minute treatment Wearable compression electrode garment pairs with BioWave's high frequency neurostimulator (sold separately) to go deep into tissue and block pain Helps relieve acute, chronic, and post operative pain on and around the knee Size large XL fits knee circumferences of 15 1 2 to 19