Threading Application Guide Laydown Threading Laydown Square Shank Toolholder Sizes: Cresting (Full Profile):• Metric — 8–40mmUN 48–8 TPI External Threading ISO 0,5–5,0mm pitch 60° Partial Profile: UN 48–4 TPI ISO 0,5–6,0mm pitch Laydown Boring Bar Diameters: Cresting (Full Profile)• Metric — 12–50mmand Partial Profile: Internal Threading • Minimum bore — (13mm) UN 48–8 TPI • Steel and carbide ISO 0,5–5,0mm pitch 60° Partial Profile: UN 48–4 TPI ISO 0,5–6,0mm pitch 55° Partial Profile: UN 48–5 TPI ISO 0,5–5,0mm pitch widia.com F3