Flange Vented Plug for M6 to M8 Screw Holes, Ød4 to ØD8.5mm, 21mm Long, Silicone (Yellow), Pack of 10, HBGS0608-P
SGD $8.00
Every flange-vented plug is conical and hollow for a flexible fit. They have an exhaust port to release air expanded by high temperatures. The flange prevents excess paint from adhering to the area around the holes.