1) Akron cuttings 2) Firestone features 3) Grooved surfaces of tires 4) Grooved tire surfaces 5) Groovy patterns 6) Parts of radials 7) Radial features 8) Radial patterns 9) Radial surfaces 10) Risers meet them 11) Running shoe features 12) Sets foot 13) Sneaker bottoms 14) Stair parts 15) Steps or stairs used on stage 1) Footsteps 
Steps or stairs used on stage. 
The horizontal part of steps.
See steps.