Flange Conical Plug (EPDM) for M26 to M33 Screw Holes, (Ød2)23mm x (Ød1)36mm, 20mm Long, EPDM (Black), Pack of 10, HBJE360-P
SGD $6.00
These masking plugs have a flange to protect the surrounding area around the hole from treatment processes. You may also use them for holes with small counterbores if the dimensions fit.