It did work with my old USB sticks & mouse but some powered USB’s (v.3) devices didn’t work and it didn’t keep my iPad charged up (just slowed the drain).
I ended up buying an Apple version which didn’t have these issues.
If you want to use it with iOS 13 & it’s new Files system buy the Apple one; if it’s for older iOS using a USB v.2 device this may work for what you need to do.