A device employed by a user for applying a self-adhesive product to a surface, the device comprising: an outer housing (102, 202) configured for gripping by a single hand of the user, the outer housing having a distal end (108, 208), and a proximal end (104, 204); a volume of self-adhesive product disposed within the outer housing (102, 202); an automatic dispensing mechanism disposed within the outer housing and operatively coupled to the outer housing (102, 202) and the volume of self-adhesive product, the automatic dispensing mechanism configured to advance at least a portion of the volume of self-adhesive product through the outer housing distal end (108, 208) in response to a manual actuation force applied to the outer housing; wherein the outer housing (102, 202) defines a longitudinal axis, and in which the manual actuation force includes at least a force component parallel to the outer housing longitudinal axis; wherein the device further comprises an inner housing (116, 216) slidably disposed within the outer housing (102, 202) for holding the volume of self-adhesive product and having a dispensing end (122, 222) positioned distally from the outer housing distal end (108, 208) and defining a discharge orifice (122, 222) through which the self-adhesive product is advanced; said outer housing (102, 202) being distally slidable relative to the inner housing to an actuated position; wherein the automatic dispensing mechanism comprises a guide rod (134, 234) extending through the inner housing (116, 216) and having a proximal end (104, 204) coupled to the outer housing (102, 202), and a plunger (132, 232) disposed in the inner housing (116, 216) and coupled to the guide rod (134, 234) at its distal end; wherein movement of the outer housing (102, 202) in a distal direction relative to the inner housing (116, 216) slidably advances the plunger (132, 232) through the inner housing (116, 216) to a distal position; wherein a stop is formed at a distal end (120, 220) of the inner housing (116, 216), wherein the stop is configured to limit distal travel of the outer housing (102, 202) thereby to define the actuated position of the outer housing; in that wherein the distal end of the guide rod being slidably coupled to the plunger to permit movement of the guide rod in a single direction with respect to the plunger; characterized in that said proximal end (118, 218) of the outer housing (102, 202) includes an aperture sized to releasably engage the guide rod (134, 234), and in which the guide rod includes a head positioned proximally of the aperture, wherein the aperture is configured to release the guide rod (134, 234) in response to an unloading force applied to the rod head. an outer housing (102, 202) configured for gripping by a single hand of the user, the outer housing having a distal end (108, 208), and a proximal end (104, 204); a volume of self-adhesive product disposed within the outer housing (102, 202); an automatic dispensing mechanism disposed within the outer housing and operatively coupled to the outer housing (102, 202) and the volume of self-adhesive product, the automatic dispensing mechanism configured to advance at least a portion of the volume of self-adhesive product through the outer housing distal end (108, 208) in response to a manual actuation force applied to the outer housing; wherein the outer housing (102, 202) defines a longitudinal axis, and in which the manual actuation force includes at least a force component parallel to the outer housing longitudinal axis; wherein the device further comprises an inner housing (116, 216) slidably disposed within the outer housing (102, 202) for holding the volume of self-adhesive product and having a dispensing end (122, 222) positioned distally from the outer housing distal end (108, 208) and defining a discharge orifice (122, 222) through which the self-adhesive product is advanced; said outer housing (102, 202) being distally slidable relative to the inner housing to an actuated position; wherein the automatic dispensing mechanism comprises a guide rod (134, 234) extending through the inner housing (116, 216) and having a proximal end (104, 204) coupled to the outer housing (102, 202), and a plunger (132, 232) disposed in the inner housing (116, 216) and coupled to the guide rod (134, 234) at its distal end; wherein movement of the outer housing (102, 202) in a distal direction relative to the inner housing (116, 216) slidably advances the plunger (132, 232) through the inner housing (116, 216) to a distal position; wherein a stop is formed at a distal end (120, 220) of the inner housing (116, 216), wherein the stop is configured to limit distal travel of the outer housing (102, 202) thereby to define the actuated position of the outer housing; in that wherein the distal end of the guide rod being slidably coupled to the plunger to permit movement of the guide rod in a single direction with respect to the plunger; characterized in that said proximal end (118, 218) of the outer housing (102, 202) includes an aperture sized to releasably engage the guide rod (134, 234), and in which the guide rod includes a head positioned proximally of the aperture, wherein the aperture is configured to release the guide rod (134, 234) in response to an unloading force applied to the rod head.