But right now I am using the ORIGINAL Samsung 1800mAh battery of Epic-Touch-4G... It is slightly bulkier than the one came with glide... But fits TIGHTLY with the glide's original cover without any issue... Initially you may find it tough to close the back, but don't worry, it will fix like glove and phone will work perfectly... I am using this now in my glide...

The original glide 1650mAh battery + cover will have half or one mm play (gap) initially.. After placing the 1800mAh battery of Epic-Touch, that gap was gone and phone battery life is also improved a little bit...