Tubular sewn-in "J" buttress with dynamic side-pull compression strap to support patella malalignment. 1/8" neoprene for warmth and compression. Sold in right and left configuration.
Measurements
Measurements taken 6" above mid-patella

Sizing:
S 15 1/2" - 18"
M 18"- 20 1/2"
L 20 1/2" - 23"
XL 23" - 25 1/2"
XXL 25 1/2 - 28"