A protective enclosure for use with one or more electric cables (10, 12) comprises first and second elongate casings (16, 18) juxtaposed along respective end surfaces thereof to define a housing with an open interior, at least one electrical cable (10, 12) disposed in the housing interior in an encapsulant, the encapsulating filling the housing interior. At least one end closure (20, 22) is disposed in the housing and defines a cable passage therethrough, the cable being resident in part in the cable passage. Seal-effecting structure for providing sealed relations (16a, 16b, 18a, 18b, 28) between first and second casings (24, 26), between the end closure and the first and second casings and (46) between the end closure and the cable part, is inclusive of a cover plate disposed in confronting relation to the end closure and movable relative thereto.