This battery brought my now 15 year old iPhone back to life. It is a bit tighter fit than the last battery but charges and runs well. Expect a bit less life than original.
Battery fit and works fine. Instructions would be nice, but they do tell you it is not a DIY item. Plenty of room for loose wires to be tucked in.
You can't use the old wires because the connections of the new wires are further away.