Why Did You Choose This?
Purchased for my Speedlight 580 EX II. Work great! Be aware, if your flash all of a sudden stops firing and you think there is still juice in the batteries, pull the batteries out. They will likely be hot which is why the flash stopped functioning. If you let them cool, you can put them back in and everything will be back to working.
Simply the best when it comes to rechargeable batteries. The last, and maintain their charge better than the competition.