I accidentally received a 100 amp battery without Bluetooth. I wrote to customer service and they replied that I could exchange it for one with Bluetooth. When I asked for a price for a return label it cost €45 + €10 for what they had sent me. I had to push them for this answer as it took a week before they sent this option. It is simply super bad customer service to set the price so high. I will never buy from this company again. Now I will give the battery to someone who will take it apart and