When you start to make or design a bra, it’s natural to question the job or function of everything we see, that is usually in the same place of the bra.
*Although please don’t just commit and keep it the same, some awesome designs come out of mixing it up and pushing boundaries on what we usually see.
The ring and sliders have been on lingerie since the 1800s, with the most common shape for the ring being a circle. Standardly cup sizes A & B would have rings at a size 8mm or 10mm, and the bigger bra sizes would usually use 12mm and 15mm.
The rings are usually found on the back of the bra where the back strap meets the wing, the reason why is because it acts as a joint. The circular ring allows the strap to move, so the angle that the strap goes up towards your shoulder, can alter through movement and through different body shapes, ie be able to move towards the inner or outer shoulder.
The strap can be in one continuous or two split pieces of strap, as the front strap can be more decorative and the amount that it stretches is less of a concern, (ie it can have limited stretch if you desire). But the back strap needs to have durability when stretched.
Extra rings can be used at the apex (where the cup meets the strap) or joining two straps together if there are two different straps being used. Unlike the slider where if the strap is 15mm the slider has to be 15mm, rings can be smaller than the strap.
Usually without the ring at the back depending on your body shape you can feel the strap where it leaves from the wing.