Seamless bras - usually found in sports bras, are made on the Santoni circular knitting machine. This machine can knit shaped panels and being circular it can be seamless i.e. without seams at the side. The structure can be adjusted through the use of different knit structures such as a knit, purl or tuck. A wide variety of fabric structures, garments, hosiery and other products can be produced in a variety of diameters on circular knitting machines. Stitch structures such as tucks, floats, and false ribs are used to modify the shape of a tube, the lengths of stitches or unbalancing the structures can also have an effect.
While the underbust is rib finished without a seam, there is often a stitch around the neck line and also at the joint of the front and back straps.