Instruction: Given a question and the related document, and generate the answer to the question based on the information provided in the document.

Input:
Question: life span
Document: I've had the Panasonic KX-TG5432 Model w/ two handsets for about 6 years. I work from home and use them extensively for teleconferencing as they have the headset feature on the handset. Some days my meetings may span 6 to 8 hours which two phones could handle easily. However, over the last year or so, the battery life of each unit has gradually reduced to 1 to 1 1/2 hours fully charged. Rather than get a new phone, I decided to order these replacement batteries first.
Battery life is excellent.
Works like a charm and with it my old panny got back to second life.
I assume that the life will be as long as the originals (almost 5 years) or longer.
its just a battery. it seems to be working fine.an exact match to the original. i haven't had it long enough to determine its life.
brought new life to my old phone at a fraction of the cost of buying the battery at a local store.
This was a life saver as it solve my problem without having to buy a new phone my phone is now good as new.
This battery has met all of my expectations. It has extended the life of my Panasonic cordless phone which is about 11 years old or more.
The life of my original phone battery fell to about an hour, so I ordered this replacement. Worked as expected.
Perfect replacements for my Panasonic cordless set. Now my battery life is back to what I used to have when they were new.
Answer: I replaced mine after approximately 5 years of normal use and regulAr recharging.