Seismic Speed Vent Longboard Wheels for Cruising, Downhill, Electric Skateboard Colors THE ULTIMATE HIGH SPEED WHEEL - Seismic Speed Vents are hands down the fastest large longboard wheel. Whether you're using them for long distance pushing and cruising, downhill or on your electric skateboard, these things are undoubtedly fast. GRIP OR SLIP - When the skin is fresh, these wheels are super grippy and will lock you into corners without scrubbing. When broken in these wheels slide like butter. They're great for super long standup slides, as well as, dialed in drifts. THREE DIFFERENT FORMULAS - BLACKOPS: For the ultimate speed and pure grip. Does not slide as smooth. | DEFCON: Explosive speed with smooth, predictable grip to drifts and slides. Lasts super long. | CLEAR - Enhanced rebound, tons of roll speed, dumps urethane. DUROMETERS - BlackOps: 76a, 78a, 79a | DefCon: 77a, 78.5a, 80a | Clear: 75a, 77a, 79a SPECIFICATIONS - 73mm x 54mm | 77mm x 55mm | 85mm x 52mm