A pound and some change. Only the vaguest tread on the back end - clearly the surround is there to stabilize the shoe on the latch and not as a platform pedal

https://c1.staticflickr.com/5/4221/3...d98516eb_c.jpg
Untitled by Darth Lefty, on Flickr

https://c1.staticflickr.com/5/4267/3...571be52f_c.jpg
Untitled by Darth Lefty, on Flickr

Bump with news. I installed these on my MTB, not my commuter, for starters. Their action is very light. The plastic platform provides some good support that seems like it would be less comfortable if the platform were aluminum. I like them. But they're definitely still full time SPD's. I might buy another pair if the sale is still on.

edit: sale over! You can find them for $30 at Merlin today, though.