This is a after market Adapter to fit the Canon SX30 & SX40 bridge cameras. It's a perfect fit, and is well made, Top Marks! Why pay £30 for the Canon one, when this one does the same job perfectly for £10-12 This allows you to use any 58mm filter you wish on the camera, keep a UV filter on at all times. This is not as many people seem to think to stop UV light reaching the lens, but to save the lens from being scratched or damaged! Beware if you damage the lens you may as well throw the camera away! keep a UV on at all times. Remember to buy a 58mm lens cap! SX50 up date : Canon list their own adapter "FA-DC67A" as fitting the SX30,40 & 50. So clearly it's the same fitting! so should fit the newer SX50 as well.