My laptop started having problems charging, and I was not sure whether it was the connected in the laptop or the charger. Lenovo sells these chargers at $50 a pop, so I decided to try Amazon.com at about a half of the price. It works great!
I bought this for a Lenovo Thinkpad T410. Worked perfectly. This is the only adapter I would recommend for the t-series of laptops with the large plug. I bought a previous that was supposed to work and it had a small plug. Make sure you need the larger plug.