Shimano SPD pedals & cleats questions??

[Telkwa]

OK, I've only got a few SPD pedals and I'm already confused.

First off, what terminology is used to describe the little metal piece that connects to the shoe? Is that the cleat? I think that's the right word.

I've got three different cleats in front of me. H20, SM-SH51, & SM-SH56. I'm not really sure where they all came from.

Google "Shimano H20" and you'll get very few hits so I think H20 might be some aftermarket piece, not Shimano.

I have a pair of old XLC-branded mtn. pedals. They're multi-use, with SPD clips on one side and standard cage on the other. The H20's won't clip in, but SM-SH51's and SH56's do.

I have some newer Nashbar-branded multi-use pedals that will accept H20, SM-SH51, and 56. Sold as "Nashbar Double Track" pedals, not showing up on their website right now. I kept the receipt and the instructions. I wonder if the H20 cleats came with the Nashbar pedals?

I'm pulling my hair out trying to figure out how many different SPD permutations exist.

Since the 51's and 56's work with the pedals I've got, the mystery H20's seem to be the biggest problem.

 

[zoomzoom]

No idea what the H20's are. I'd leave them on the shelf.

SH-51 are single release cleats, SH-56 are multi release. Many prefer the 56 for commuting/city due to how easy they are to unclip. But that also means sometimes you can unclip inadvertently when you don't want to.