85 Ciera Prop ??? Volvo Penta

[gwalkgwalk]

I have a 1985 Bayliner Ciera with a Volva Penta engine. How do I know which type of prop to buy to replace it. I can't really read what the orginal prop says. I think it says 15x17. The boat also came with a extra steel prop. But this one says 15 1/4 x 17 LH (I believe) When I put the steel one on it doesn't turn as freely as the orginal one??? How do I figure this out so I can buy a new one.

Also the steel one looks like its a thru hull ex. while the orginal one isn't.