Prop pitch?

[Sheephead Slayer]

My 1984 Evinrude 25 horse has 9.2-12 on the hub. I have no idea what that means, is this the prop I need? My R.P.M seems kinda low, maybe theres a better choice?
Thanks
Kevin

[Mr. Pike1]

The numbers you are seeing most likely are the first number the diameter of your prop and the second number is usually the pitch. There is not perfect pitch it all depends on your needs. A higher pitch will give you better top end speed but will reduce your hole shot. Make sure to stay with in the mfg recommended top end RPM's