SainSonic S3 Wireless Charger The coolest addition to your S3, charge as fast as the microUSB cord did. Ultrathin design, compact and light weight without increasing additional weight of the S3. Adding wireless charging feature by piggybacking the Energy Card on the battery of S3, it work well with any Qi-enabled charger. Easy assembly and disassembly, convenient to use in 3 steps as follows: Take off the back cover, attach the Energy Card on the battery, put on the back cover. Energy Card can be attached at all time without removing it frequently and would not interrupting the normal use of S3.