H-STRUT Closure Strips (C-900) are UL Listed and are designed to fit all H-STRUT channels to make a surface raceway. Electrical Fittings are also designed to fit all H-STRUT channels. The C-900 closure strip is used as a cover plate for closing slotted area of H-STRUT. It is inserted before or after installation. The closure strip fits all H-STRUT channel sizes.