Mustad now offers a hollow, splice-able microfilament line. The hollow core design allows monofilament to be spliced into the braid for the strongest possible main line-to-leader connection. This is a must for "top shotting" monofilament into the braid. Simply insert the end of the monofilament approximately two feet into the braid and use floss to whip the area where the mono enters the braid. Use for making wind-on leaders or as a backing for top shotting with monofilament.