My Nokia N8 started turning off by itself and it dies in 5 hours after its fully charged. The T4 Screw driver was the perfect the size to open up the phone but I think my phone had a different problem besides that. The point is though, the screwdriver was perfect and it was great.
It didn't really go the way I wanted it to go. The screw driver did its job just fine, my phone was just in time to go.
I think Nokia N8 phones are really not meant to have their batteries replaced.