Most long-sleeve baby bodysuits are 100% cotton. There are also cotton blends (for example 95% cotton/5% spandex) and some styles made from 100% polyester thermal fabrics.
Common sizes include NB (newborn), 0/3M, 3/6M, 6/9M, and 12M for infant long-sleeve bodysuits.
Common necklines are V-neck, lap-shoulder (expandable) necklines, and scoop necklines, depending on the design.
Bodysuits typically use crotch/bottom snaps and expandable lap-shoulder necklines to speed up diaper changes.
Fabric weight ranges from lightweight to midweight. Some listings include specific GSM values for fabrics (for example 200 GSM or 220 GSM) for particular items.
Care instructions commonly state machine wash and tumble dry for infant long-sleeve bodysuits.