Abstract: Adjustable clamp systems that include friction sleeves and corresponding compression nuts for securing the friction sleeves to an elongated support structure. Each friction sleeve is designed and configured to slidably engage around the exterior of the elongated support structure and includes at least one deformable region that allows the corresponding compression nut to radially compress a portion of the friction sleeve into firm engagement with the support structure so that the friction sleeve firmly grips the support structure. The adjustable clamp systems can be used to secure one or more objects to the elongated support structure.