These are the screws I used
My pair of Adidas Kanadia TR 3 Winter
20 screws on each shoe
I went for a short 3K run to test these bad boys. There were patches of ice because we had a freezing rain 2 days ago and the temperature dropped so that the snow was hard. A perfect scenario to try them out.
If feels strange because of the noise on the asphalt, and on the ice you really have a grip BUT (there's a big BUT) you have to be careful. Change of pacing is inevitable. I didn't fall but there were times that I felt my shoes slipping.
Now, when I changed the surface where some parts were packed snow and some other were a mix of icy patches and snow under, then, these shine. The grip is amazing. I could speed up the pace and did some testing like stopping in an emergency, and it held well.
To summarize, yes, you can run on black ice and the screws will grip on it, but, be careful. It's still slippery.
On a mix of packed, icy snow, these are excellent.
I'm considering maybe put some more on the front of the shoes to have an even height. When I was on the road, I could feel the difference.
Happy running folks!!!
