Solar Masthead™ Cordgrips The Heyco Solar Masthead™ Cordgrips are designed to replace rooftop combiner boxes in solar rooftop installations and accommodates XHHW-2 12 AWG and 10 AWG wire. Less expensive, easier to install, and more aesthetically pleasing, the Heyco Solar Masthead Cordgrips are threaded into an adapter that allow the cordgrips to be attached directly to rigid (PVC) or EMT type conduit. The cordgrips provide a watertight seal for PV module output leads to inverters, secures input PV leads from solar panel array strings to fuse holder hook up within solar combiner boxes, and features generous wrenching flats for ease of assembly.