ZWXJ Brand New from manufacturer. Rechargeable up to 500 times over life of battery. Battery type: Li-Polymer battery, voltage: 14.8V, capacity: 40WH Ce-/RoHS-/FCC- certified and built-in circuit protection ensure both safety and stability. Fit for: inspiron 14 Series 14-3421 14-3437 14-5421 14r-3421 14-n3421 14-n5421 inspiron 15 Series 15-3521 15-3537 15r-5521 15R-5537 15r-n3521 15r-n5521 15r-n5537 inspiron 17 Series 17-3721 17r-5737 17r-n3721 17r-n3737 17r-n5721 17r-n5737 latitude E3440 E3540 Series Vostro 2421 2521 Series 100% customer satisfaction guarantee: We believe in quality and Customer service, and our top priority is to make you happy. If for whatever reason you are not fully satisfied please contact us and well guarantee to help. We have 12 months warranty on our products.