Designed to help with larger add-in components. The Clamp e-blox is fabricated from 6063 Aluminum, which is black anodized.  It is available in the above sizes.  Clamp e-blox are used to sandwich a rail system between it and another e-blox. This e-blox can make a quick swivel mount and or a good structural joint.  This is used for heavy clamping were the half clamp can be used in the lighter applications.