The Kingston 4GB CompactFlash Memory Card Elite Pro 133x memory card is designed specifically to help advanced amateur or professional photographers get the best performance from their high-end imaging devices and applications. The autosleep feature of the cards preserve system battery life. No matter how fast you work, the Elite Pro cards can keep pace with its ultra-fast transfer rates of 25MB/sec. read and 20MB/sec. write. The cards high capacity means you can capture more continuous, high-resolution images, and when it's time to transfer your largest files, the high speed rating of these cards means that your production workflow will be more efficient than ever.