last year I bought an extra large and an extra extra large. I don't know if I specifically went to their website to find which science or just went off of Sierra, but the extra large worked well on my bogs Arcata size 10(or 11) (flared tread base) and I got the XXL for my enormous Baffins - specifically the kind you can stand still in & still be warm in in New England. I don't think I would slip in those as easily but I still don't want to break or tear anything, and I don't have to "remember" to be careful so much as just put them on because eventually I'm going to get distracted and relax when I'm walking. So if it got warm enough to melt any before it refroze overnight, I just wear them every time.
I will see if the spikes were tiny. it might be harder to remember to take them off when I went inside. and some people reported that those cool ones that are integrated in the bottom of boots that I felt all seemed to run a bit narrow for my wide feet, sometimes people lose the key that allows you to flip them and other times they get stuck or break off* *I hear that's primarily because people forget to use that so-called key to swipe all the snow and ice out of the channel before they swap them. just putting it out there.

Bought these for my boys to enjoy hiking in the snow and ice. Spikes are well made and performed perfectly. Sizing is pretty accurate and fit both boys boots 2/2.5.

Good