They work really well. Wie erwartet, these appear to be made by dji. I have compared them to my oem props and cannot tell the difference Music. There are lots of cheaper versions out there, but i decided to spend just a bit more and get the real deal. I am glad i did. These are perfect replacements for the spark, and i have no worries about them, not fitting properly or flying off. When i am in flight, i would highly recommend these blades for anyone who owns a spark. The spark is not a toy and should be treated as such. Only genuine replacement parts for me. Would you risk hundreds of dollars to save five imaging your quadcopter as 200? In the air going 20 Meilen pro Stunde, a blade fist do not buy fake carbon fiber blades these things flex so far when in flight don’t risk it dji props, they are the same ones. You get from dji that are dji. Props will definitely order again. I ordered this item to have as extras in case of an unfortunate hard landing or crash into a stationary object. Items arrived on estimated date of arrival, packaged well and intact, always good to have extras on hand. Factory dji propellers for the spark Music can’t really complain about anything other than the price.