Based on this product's specifications, here are some alternatives and similar models
Battery Origin Storage Latitude 5421 4210 mAh 64 Wh Lithium-Ion Black
Summary description:
The Origin Storage 4C Battery for Latitude 5421 offers a capacity of 4210 mAh and 64 Wh. It utilizes Lithium-Ion technology and has a voltage of 15.2 V. This black battery is designed for reliable performance and longevity, making it an essential accessory for your laptop.