A flashlight assembly for use with a pistol having a dovetail rail forward of the trigger comprising: a housing having a forward end and a rearward end and a battery opening in the rearward end for receiving at least one battery therein; a dovetail rail clamping assembly on an upper side of said housing; a light assembly received in the forward end of the housing; a battery door assembly comprising: a body portion having a forward side and a rearward side, the forward side being receivable within the battery opening in the housing, a latch pin received into a top portion of forward side of the body portion, the latch pin having a latch head and groove at the front end, the latch pin being slidably received into a longitudinal guide hole in a top portion of the rearward end of the housing, said latch pin allowing the battery door assembly to slide longitudinally relative to the housing and to rotate relative to the housing about the latch pin; and opposing paddle actuators received on a rearward side of the body portion and operating about vertically oriented hinge pins; and a spring biased latch button received on said upper side of said housing, said latch button including a latch shoulder disposed for traverse movement across the guide hole, said latch button being movable between an outwardly biased and latched position and an inwardly actuated unlatched position. a housing having a forward end and a rearward end and a battery opening in the rearward end for receiving at least one battery therein; a dovetail rail clamping assembly on an upper side of said housing; a light assembly received in the forward end of the housing; a battery door assembly comprising: a body portion having a forward side and a rearward side, the forward side being receivable within the battery opening in the housing, a latch pin received into a top portion of forward side of the body portion, the latch pin having a latch head and groove at the front end, the latch pin being slidably received into a longitudinal guide hole in a top portion of the rearward end of the housing, said latch pin allowing the battery door assembly to slide longitudinally relative to the housing and to rotate relative to the housing about the latch pin; and opposing paddle actuators received on a rearward side of the body portion and operating about vertically oriented hinge pins; and a body portion having a forward side and a rearward side, the forward side being receivable within the battery opening in the housing, a latch pin received into a top portion of forward side of the body portion, the latch pin having a latch head and groove at the front end, the latch pin being slidably received into a longitudinal guide hole in a top portion of the rearward end of the housing, said latch pin allowing the battery door assembly to slide longitudinally relative to the housing and to rotate relative to the housing about the latch pin; and opposing paddle actuators received on a rearward side of the body portion and operating about vertically oriented hinge pins; and a spring biased latch button received on said upper side of said housing, said latch button including a latch shoulder disposed for traverse movement across the guide hole, said latch button being movable between an outwardly biased and latched position and an inwardly actuated unlatched position.