Exell 4.8V 170 mAh Battery for SPORTDOG 650-058 FIELD TRAINER SD-400 RECEIVER FIELD TRAINER SD-400S RECEIVER MH120AAAL4GC WETLAND HUNTER SD-400 CAMO RECEIVER WETLAND HUNTER SD-800 CAMO RECEIVER 170mah 12 month warranty User Replaceable battery pack rechargeable