This Battery replaces the Sony part NP-FS21 and is a Lithium Ion rechargeable Digital Camera Battery.This high-capacity rechargeable lithium-ion battery is a replacement for Sony NP-FS21 battery. It features lithium technology, which ensures maximum battery life and maximum power. It also features no memory loss effect that lets you recharge partially drained batteries without reducing performance.Please note:Our compatible battery fits other devices not necessarily listed here. Please see your instruction manual for your battery part number.This battery is compatible with the following cameras.DCR-PC1 DCR-PC1E DCR-PC2 DCR-PC2EDCR-PC3 DCR-PC3E DCR-PC4 DCR-PC4EDCR-PC5 DCR-PC5E DCR-PC5L DCR-TRV1VEAll our digital camera batteries are manufactured to the highest standard. They are all fully compatible replacements of the original and in most cases offer a higher capacity and are fully guaranteed for 2 years.