I haven't used it since I bought it. It's been about two years, so I'm not sure if the disposable warmer inside is still usable, but it's a new, unused item ◎ A cozy disposable warmer case with a disposable warmer, perfect for small animals - Product Name: Cozy Disposable Warmer Case - Included: 1 disposable warmer - Purpose: Heating device for small animals - Temperature: Approximately 40°C (when in use)