Common capacities include 4 fl oz, 5 fl oz, 6 oz, 8 fl oz and larger sizes up to 32 ounces. Bottles are sold as single items or in multi-bottle sets.
Nipples are typically made from silicone and are offered in graded flow levels. Examples from listings include Level 1 (slow flow), Level 3 (medium flow), and some systems that provide numbered flow options from 1 to 5.
Common extras include feeding nipples, silicone sleeves or soft silicone coatings for grip and protection, lids, pour spouts and dispenser caps. Included accessories vary by product and set.
Bottles made from premium borosilicate glass are noted for thermal and heat-shock resistance and can withstand hot and cold temperatures. Many listings say these bottles are suitable for warming, refrigerating and sterilizing.
Glass bottles commonly come in wide, standard and narrow necks. Wide-neck designs make filling and cleaning easier, while standard or narrow necks match different nipple styles.
Many clear glass bottles are dishwasher-safe (often top-rack). Product details also list boiling, steam, or electric/microwave sterilizers, as well as hand-washing with soap and a bottle brush. Most listings advise washing before first use.
Common labels include BPA-free and other "free-from" claims such as phthalate-free, BPS-free, PET-free and lead-free. Some listings also specify PVC-free, nitrosamine-free or latex-free; labeling varies by product.
