flexikold gel cold pack (oversize: 13 x 21.5) - a6302-cold - (x-large) by flexikold flexikold 4 sizes: standard, oversize, half size, & neck contour;colder for longer: proprietary gel stays colder for longer than competing products that use inferior bentonite formulations.;more flexible: the most flexible cold pack available due to a professional-grade gel interior that remains pliable when frozen, which provides better contact by conforming to any part of the body.;healthcare professional's choice: used by thousands of physical therapists and other healthcare professionals to relieve acute & chronic pain, muscle pain, arthritis, inflammation, and swelling, and aid injury recovery.;premium construction: double sealed to prevent leaking; with extra thick nylon exterior that will not crack like vinyl exteriors. washable and reusable.