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.