Radio Systems Corporation Recalls Power Adapters Sold with PetSafe® Heated Wellness Sleepers Due to Fire Hazard This recall involves the Class 2 Transformers that were sold with PetSafe Heated Wellness Sleepers. The power adapters are identified by the markings "PLUG IN CLASS 2 TRANSFORMER," "MODEL NO: K12-800" and have a spring coil covering the length of the electrical wire that goes from the sleeper. Power adapters without spring coils are not affected by this recall.