Findings are used in the making of bra straps, and suspender straps. All fittings are based on the aperture diameter (the internal width of the hole or slot), so relate directly to the size of strap you should use. That is: If your strap is 12mm wide, you would use a 12mm slider etc. You may be able to use a slider slightly narrower or wider fitting than your strap width, depending on the thickness and type of strap.
Because rings are round, it is not uncommon for people to use a size smaller than the strap, this particularly applies when using very wide strap, ie. 20mm, as a 20mm ring is huge! For 20mm and larger strap, use the correct slider and use a LINK of the same size in place of the ring if available. If you prefer to use a ring use 16mm.
Hooks are used to make removable straps, Simply make a loop on your garment using ribbon where you want to attach the strap, so you can hook it on
TIP: If you cannot find a ring or link available in a suitable size/colour to match your slider simply use a second slider in place of the ring!