Counterbore Plug, (Ød2)4mm to (Ød1)6.5mm, Silicone (Black), Pack of 10, HDCS65-P
SGD $13.70
Solid and durable, every plug fits a range of hole diameters. Use them for threaded holes or holes before dowel pin installation. The counterbore ensures that the area around the hole is protected too.