Abstract: Electric shaver of battery powered and washable type having a watertight housing structure. A battery covering detachably mounted to housing bottom opening for holding batteries inside the housing includes a lock and seal which are activated, responsive to the covering's mounting operation, respectively in directions transversing the housing axis to lock the covering to the housing interior wall and in the housing axial directions to achieve uniform abuttment of the covering to the interior wall for clamping therebetween a watertight ring seal.