La Sportiva Men’s Boulder X. La Sportiva tweaked the designs of proven technology from years past to produce the Boulder X. Additional padding underfoot for long approaches and uber sticky rubber add deluxe comfort and performance. The Vibram® Idro-Grip compound stays sticky on every type of rock even when wet. The all leather uppers and sticky rubber toe rands offer durable protection. Ideal protection and performance built for the rigors and abuse of the mountains.