Traction, traction, traction! With 8 legs gripping the ground the traction is unmatched. Yet the spike has a soft flex for maximum comfort. Specially formulated polyurethane for long wear. Of course the spike is easy on the greens too. The disk pack of 18 spikes has the Slim-Lok system which fits any Fast Twist or Tri-Lok system shoe. We can tell you which system you have, just call if you're unsure.