A hand-held portable data entry terminal is encased by an elongate housing of substantially rectangular dimensions. The housing includes upper and lower housing shells which are assembled into a water tight housing. The upper housing shell supports on an upper surface a display and a keyboard with typically alphanumberic keys. The area taken up by the display and keyboard defines an overall width of the data terminal which may exceed the width of a readily hand fitting grip. The terminal consequently includes in a central portion of its lower housing shell a grip conforming portion of an inwardly displaced lower wall bounded by inwardly converging angled sidewalls. The depression in the center portion of the housing adjacent opposite end portions is spanned by a resilient strap disposed longitudinally across the grip conforming portion. A user may insert a hand into a space defined between the strap and the inwardly displaced surface. The strap enables a user to relax the grip on the terminal without the terminal being released from holding engagement of the data terminal with the user's hand. A battery pack inserted from a bottom end into a battery compartment at a bottom end of the lower housing shell is suitably mounted externally of a sealed environment within the housing. Sealed contacts extending through a wall of the battery compartment into the housing engage contacts of the battery pack and couple power supplied by the battery pack to the circuits of the data terminal within the sealed environment of the housing. The battery pack includes a plurality of external contacts for coupling an external battery charger to the battery pack, for initiating the charging process and for providing access to data transfer circuits through the battery pack to the interior of the data terminal.