content: So this Mueller shoulder therapy was not what I originally ordered. I ordered the Elasto-gel cervical collar. I was sent this Mueller SHOULDER cold/hot therapy......even though returned (twice, because my replacement was the same wrong item) I can tell you it is a cheap not what you are looking for product. The material is the basic pull on brace type. The hot cold pack looks like the type you crush to activate, although it is suppose to last awhile. If you need something that last and rocks, look at the Elasto-gel products. I ordered the cervical collar for my husband. It to me seems like it does not get that cold, but he begs to differ. He has chronic neck pain due to an old softball injury and still plays so aggravates it all the time. He loves the flexibility. He wraps it on and goes to bed!!