The Slime Balls Stranger Things Hellfire Club Light Ups OG Slime Red 66mm, 78a Wheels feature light up technology with Santa Cruz Slime Balls x Stranger Things Hellfire Club artwork. STRANGER THINGS Netflix. Used with permission. Slime Tech. Slime Balls Light Ups wheels feature LED lights that light up when you roll, powered by the rotation of the special wheel spacer and wheel core. No batteries required. Light Ups come with high quality removable / replaceable steel bearings. Slimeballs OG Slime shape is a versatile, symmetrical center bearing cruiser wheel with soft, 78a urethane.