Using Reduced Redundancy Storage

The Amazon S3 Reduced Redundancy Storage (RRS) option provides a less durable, highly available storage option that is designed to provide 99.99% durability of objects over a given year.

Amazon S3 stores objects according to their storage class, which Amazon S3 assigns to an object when it is written to Amazon S3. The default storage class is STANDARD. You can assign objects a specific storage class (STANDARD or REDUCED_REDUNDANCY) only when writing the objects or when copying objects stored in Amazon S3. RRS is specified per object, at the time the object is written."

For a general overview of this feature, see Reduced Redundancy Storage.