Stitch-bonding machines consolidate a pre-formed fiber web, yarn layer, or substrate by stitching through it with a warp-knit structure, producing a bonded fabric rather than a true knit. Conventional knitting machines form loops from yarn alone. The presence of a substrate or web-feeding system is the key technical indicator that a machine is a stitch-bonding rather than a knitting machine, and this distinction matters for accurate tariff classification.

Gauge — the number of needles per unit of bed width — defines the fineness of fabric a machine can produce and is a primary commercial specification. While gauge does not typically create separate tariff subheadings at the SITC level, it should be clearly stated in commercial invoices and packing lists because it supports accurate valuation, helps customs verify the machine's description, and is essential for the buyer's technical due diligence.