Fasteners, suitable for bikinis, front fastening bras, bra tops, even side fastening skirts etc! Two halves which clip together.
Colour is representative as different monitors will make colours look differently.
As with all bra fittings the SIZE refers to the aperture (the holde/slot where the strap fits), so you should order a clip the same size as your strap.
Clasps and clips are measured according to SLOT/APERTURE/STRAP size, so if you buy a 20mm clip, then you would thread a 20mm strap through the slot. You can normally get away with the strap/fabric being a big wider on your bikini, as the fabric will simply gather through the hole. (both sides included)