Sebo Walker - Perfect Switch Back Smithwww.streetleague.com Kelly Hart with a smooth Pop Shove-it Crooks. Sebo Walker with a Nollie 180 Switch 5-0 and a perfect Switch Backside Smith grind. Stoner Skate Plaza is part of the SLSF - Street League Skateboarding Foundation. If you skate any of the SLSF parks make sure to hashtag your clips #SLSF for a chance to be featured.