That's what I thought when I ordered 6 packages... I just opened my parcel, and went WTF? These are tiny little things, I was looking for 5x3 props for my 250 quad....I have no idea why they say 5030 I just hope the 6030 props I ordered are actually 6x3...
I had trouble trying to press fit these on the 1811 2900kv motors so I got a 2mm drill bit and drilled them but then they were too loose. I used the prop savers that came with the motors and built an awesome little acro quad. All the best and Happy flying!
From more research, the hole is just under 2mm, as they are designed to be push fit onto a 2mm shaft. This means very limited application. Ideally you want a 5mm hole without any adapter. Most people agree that in the 5030 size Genfam are really good and reasonably priced. Hobbyking is lacking in 5 inch multi rotor props. Now with mini quads getting real popular we can hope they will stock something as good as the genfam props.
Got those and the red ones. Turned out to be nicely balanced and they add nearly no vibrations attached to a small motor. One blade is slightly unbalanced though or maybe the center whole is not perfectly in the center.