Synergy Digital Laptop Battery, Compatible with HP 851477-422 Laptop, (Li-Pol, 11.4V, 4000mAh) Ultra High Capacity, Replacement for HP 2TT74UT, 2TT75UT, 2UA28UT, 851477-421, 851477-422 Battery - Walmart.com
Synergy Digital Laptop Battery, Compatible with DELL 9077G, H5CKD, TXD0 Laptop Battery (Li-Pol, 15V, 3450mAh) - Walmart.com
How to find the correct battery for my HP laptop?
Generic Dell Latitude E4200 11.10V 4000mAh Li-ion Battery