These have been professionally refurbished. The shell has been replaced. They all have been clean inside out. We are confident that they performed as good as new and they all comes with 6 months warranty. Check out our store for more refurbished system like this one! Free Shipping and Free return for any reason. We guarantee that you will be happy with your purchase! This model use two AA batteries. These backlit mod are picky with batteries so only use brand name alkaline batteries and the best batteries for these are rechargeable lithium AA batteries which you can buy