Yes, when steel-belted radials first became popular the most common brand was Michelin, so we called these little wires "Michelin thorns." Kevlar belts do seem to slow them down a little but they can still get through if they enter the tire just right. Good to carefully wipe your hand around the inside of the tire to be sure there aren't any little wire pieces left inside. Worst rate of punctures from them have come when riding on interstate highway shoulders. On I-5 we averaged about one flat every 40 miles - all from those little wire pieces.