Seismic Speed Vent Longboard Wheels were created with Speed in Mind. Starting from the core, Seismic created a weight-saving and Energy Conversion hub. This hub is sexy, unique, nothing out there comes close. These wheels have a 73mm diameter, enhanced rebound, and lips designed to grab the road like spiderman! These are the highest quality race wheels out there, perfect for serious riders in the downhill, GS, and hybrid slalom disciplines.