LED tubular lamp assembly comprising: a tube housing being at least partly light-permeable and having a cross section which is circumferentially closed and constant in a longitudinal direction; a PCB assembly provided with contact areas and LED-chips and being inserted in the tube housing in the longitudinal direction; and two side cap assemblies (30; 30m, 30f) provided with outer contacts (31; 31m, 31f) for allowing the LED tubular lamp assembly to be electrically connected to an electric power supply and inner contacts for electrically connecting the outer contacts (31; 31m, 31f) to the contact areas of the PCB assembly and being at least partly inserted in the tube housing in the longitudinal direction; and wherein the inner contacts are configured to slidably come into electrical contact with the contact areas of the PCB assembly upon the at least partial insertion of the side cap assemblies (30; 30m, 30f) into the tube housing in the longitudinal direction, wherein the inner contacts of the side cap assemblies are spring type sliding contacts, wherein the spring type sliding contacts are separated from one another and guided upon deflection by a tongue protruding between them, respectively, wherein the outer contacts (31; 31m, 31f) are formed integrally with the inner contacts, wherein the tube housing has two inner notches extending in the longitudinal direction, facing each other and being engaged by the PCB assembly, characterized in that the tube housing has a flat back wall forming a part of the preferably almost rectangular cross section, the inner notches being partly formed by the flat back wall such that the PCB assembly contacts the flat back wall in a direction perpendicular to the longitudinal direction. a tube housing being at least partly light-permeable and having a cross section which is circumferentially closed and constant in a longitudinal direction; a PCB assembly provided with contact areas and LED-chips and being inserted in the tube housing in the longitudinal direction; and two side cap assemblies (30; 30m, 30f) provided with outer contacts (31; 31m, 31f) for allowing the LED tubular lamp assembly to be electrically connected to an electric power supply and inner contacts for electrically connecting the outer contacts (31; 31m, 31f) to the contact areas of the PCB assembly and being at least partly inserted in the tube housing in the longitudinal direction; and wherein the inner contacts are configured to slidably come into electrical contact with the contact areas of the PCB assembly upon the at least partial insertion of the side cap assemblies (30; 30m, 30f) into the tube housing in the longitudinal direction, wherein the inner contacts of the side cap assemblies are spring type sliding contacts, wherein the spring type sliding contacts are separated from one another and guided upon deflection by a tongue protruding between them, respectively, wherein the outer contacts (31; 31m, 31f) are formed integrally with the inner contacts, wherein the tube housing has two inner notches extending in the longitudinal direction, facing each other and being engaged by the PCB assembly, characterized in that the tube housing has a flat back wall forming a part of the preferably almost rectangular cross section, the inner notches being partly formed by the flat back wall such that the PCB assembly contacts the flat back wall in a direction perpendicular to the longitudinal direction.