The battery model EB-G991ABY belongs to the Galaxy S21 which will carry model number SM-G991. The EB-G996ABY and EB-G998ABY refer to the battery model number of Galaxy S21+ and S21 Ultra which will bear model number SM-G996 and SM-G998 respectively.

Based on the leaked renders shared by OnLeaks, we know that Galaxy S21 has a total of 5 camera sensors on the back. The front side is said to feature a single punch-hole selfie camera. Leaks surrounding the device suggest that it may feature a 108-megapixel primary camera.
3C certification for the Galaxy S21 shows that it will pack a 3,880mAh rated battery capacity with a typical capacity of around 4,000mAh and supports 25W fast charging. The Galaxy S21+ will pack a 4,800mAh battery whereas the top variant Galaxy S21 Ultra will feature a 5,000mAh battery.

Samsung Galaxy S21 series batteries obtain BIS certification - 60Samsung Galaxy S21 series batteries obtain BIS certification - 96