Keep your pooch comfy and warm with the Snuggle Puppy Replacement Heat Packs! Instead of purchasing one at a time, the multiple pack offers economical savings. Each replacement heat pack can be sealed in an airtight bag after opening for later use. Providing 24 hours of warmth at a time, simply dispose of it in your garbage can after the 24 hours are up, and since it has no smell, no need to worry about any unwanted odors.