Smooth, flowy and fast terrain? WTB's Frequency TCS i19 Rim is your guy. Its svelte weight is perfect for spinning up steep climbs and its 19mm width is ideally suited to fast cross country tires. It's made of 7000-series aluminum with WTB's legendary I-Beam reinforcement and 4D drilling for awesome lateral and torsional strength and durability. And, the Frequency utilizes WTB's Tubeless Compatible System which means with their tubeless-ready rim strip (sold separately), you can run a tubeless-compatible tire for easy conversions, minimal weight and maximum traction out on the trail.