The Schneider Electric 5590341 is a halogen-free plastic joint cover for K 161-3 TEK surface trunking, sized to a 67.2 mm cover width and matched to 72 mm trunking depth. It snaps onto the cover to bridge butt joints and continue the surface run cleanly, rated IP20 and specified for -20 to +60 C operation. Typical applications include commercial and residential surface wiring installations where trunking sections meet or transition.