What is the difference between RB and SB FireProtect 2 detectors

FireProtect 2 SB has sealed batteries. This type of detector operates for up to 10 years. After the batteries are discharged, such a detector should be replaced with a new one.

FireProtect 2 RB has replaceable batteries. This type of detector operates for up to 7 years from pre-installed batteries. After the batteries are discharged, you can replace them with new ones.