The Booster Strap wraps around the boot cuff top to secure the lower leg, eliminating the need to over tighten buckles or laces. The Booster instantly improves ski and snowboard control by dynamically bonding the calf to the boot, providing increased rebound power and turn initiation precision. All Models have a metal cam buckle for super easy closure. The Booster Strap will: Revitalize boots that have become sloppy with age Elastically bond boot to leg Provide better response without excesive buckle tension Eliminate upper cuff looseness Reduce shin bang Junior: Double band strap wmetal hardware sized for juniors and those with smaller boot sizes. Standard: Double band strap wmetal hardware for ALL intermediate skiers and expert skiers weighing less than 140 lbs. ExpertRace: Triple band strap wmetal hardware. Most expert or aggressive skiers should use this model.