An intravascular balloon catheter device for treating various size stenosed regions within a blood vessel is provided. A clamp located within a body of a handle assembly is movable between a clamped and unclamped position by way of a button. When clamped, an outer member is secured relative to a sheath to as to expose a portion of a balloon located on a distal end of the outer member. The portion of the balloon remaining within the sheath is restricted from inflation beyond the sheath.