Article: It is a little metal or plastic clip that you can slide up and down the length of your strap. Some slide adjusters can run the full length of the strap, while others can only run about halfway.  On a new bra, you will probably find the strap adjustor all the way at the back of the bra strap, near the bra band (the part that hooks across your back). Some bras, like most sports bras, are made from a single piece of fabric, and therefore do not have adjustable straps. If your straps are too loose or too tight on a bra like this, then there is an issue with the overall fit and you need a new bra. It is usually easier to adjust the strap if you are not wearing the bra. The adjustor will normally lie against your back, which makes it hard to reach unless you remove your bra. As the strap slides through the adjuster, the adjuster will move closer to the bra band. The closer the adjuster is to the band, the shorter and tighter the strap becomes. If you are trying on a new bra and you have to adjust the straps to the tightest position, it's not the bra for you. Your straps will stretch over time, so you need to have some room to tighten them later. Try a bra with a smaller band size. The slide adjuster should move closer to the bra cup. The closer the adjuster is to the cup, the shorter and tighter the bra strap will become. Remember that you probably won't want it the exact same length as the first strap, though. Your breasts are not identical in size or shape, so one strap may be a little tighter or looser than the other. This is completely normal and nothing to be self-conscious about. If your straps are fitted properly, they will lie flat and smooth against your chest and they will hold the cups against your breasts.  Always re-adjust your bra after you wash it, as the process may cause the slide adjusters to move.  If the straps are as tight or as loose as they can be and you are still having issues (the strap is falling off your shoulder, the straps are cutting into your skin), read the following sections to learn possible causes and how you can solve them.

What is a summary?
Locate the slide adjuster on your straps. Tighten a loose bra strap by holding the slide adjuster with the fingers of one hand and pulling front of the strap toward the cup with your other hand. Loosen a tight bra strap by holding the slide adjuster in one hand and pulling the back part of the strap away from the adjuster. Adjust the other strap. Try on your bra and adjust as necessary.