A:Answer I haven’t try this card with a canon 40D, but I think it should not be of any problem. However, if you wanna safe a little money, you can buy the CF card reader San disk ultra, which would work just as well. The files on a 40D ore not that demanding. Remember to always format your card in the camera and not with your computer.
Now, a good card reader is the Insignia which they sell here at Best Buy and or the card reader from Ugreen. I have both of them and they both work great and they feel durable. If you decide to buy the 3.0 version, make sure your computer or laptop have 3.0 ports or otherwise it would feel the same speed as a 2.0.
