The Toshiba Secondary High Capacity Battery is a 6-cell rechargeable, removable Lithium-Ion polymer battery pack designed for Toshiba Portege 2000, 2010, R100 and R200 series portable computers. It provides up to 5 hours of computing life in addition to the primary battery pack. Lithium-Ion Polymer technology is a new technology that allows for thinner/lighter notebooks, so you can take it on the road and it will never wear you down. This secondary battery can be used together with the primary battery. It snaps onto the bottom of the unit allowing a comfortable typing angle.