1. No Welding to the battery could make its life last longer and safer 2. No Circuit board in the battery 3. Battery compartment could be scalable to match with different battery length, could match with 900mAh/1300mAh/300mAh capacity, and the battery have 18350/18650 model,and all atomizers can be compatible, and the atomizer could be detachable,atomization core could be replaced