A coupling system for conduit and pipe for carrying insulated electrical cable, more particularly, a conduit coupling assembly for connecting multiple lengths of conduit in coaxial relationship. The sandal has a sole and an upper where the upper is comprised generally of straps forming a Y shape. Safety is improved by making sealing plates at respective axial ends of the casing stationary, and providing an annular peripheral seal around each sealing plate. An adhesive material is disposed between the panel portion of the outer panel and the first face of the inner panel, and a sealant material is disposed between the hemming portion of the outer panel and the second face of the inner panel. Also described is the process and apparatus for the generation of fluorine from fluorinefluoride containing solids, liquids or gases. Both of the preparation surfaces are mobile so as to bring alternately the respective product-intake end into a position corresponding to the product-output end of the feed surface.