The Cardellini Card-a-Link is 2.25" coupler can be used to link two clamps together ,or to attach a 5/8" pin either 90 degrees or parallel to the baby pin of the clamp. Very light weight, tightens with a 3/16" allen wrench, or will accept any 3/8-16 knob.
WARNING: This product may expose you to chemicals which are known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov.