I purchased these separately in April 2024, two sets at a time. The previous owner used each set once or twice. While breastfeeding my older child, I used to wrap small ice packs in a towel and cool my breasts, but I bought these thinking they would be convenient. I used them at the hospital where I gave birth, and they were very convenient because I could easily adjust the cooling points. I switched to formula feeding soon after giving birth, so I used these less than 5 times. I then stored them at home. The covers have been washed and are clean with no stains. Having four allows for rotation, which I think is very convenient. Set Contents: ◯ Main body: 4 ◯ Covers: 4 Shipping method may change (all are anonymous shipping). Thank you for looking.