Ice Pack for Hot & Cold Therapy Gel Pack - Hot & Cold Relief, Reusable, Freezable & Microwaveable, Pain & Muscle Soreness, Arm, Leg, Knee, Shoulder, Back Pain Relief, Compression Pack & Strap Our cold packs for injuries can be used as a knee ice pack, an ice pack for shoulder, back pain, or neck pain, or can be reused for injuries where swelling occurs. Substitutes as an ice bag for freezer storage or as a microwaveable heat pack.