1.1 This specification covers semirigid, flame-retardant, crosslinked poly(vinylidene fluoride) heat-shrinkable tubing for electrical insulation purposes. It is supplied in an expanded form and will shrink to its extruded diameter when heated.Note This specification covers semirigid, flame-retardant, crosslinked poly(vinylidene fluoride) heat-shrinkable tubing for electrical insulation purposes. It is supplied in an expanded form and will shrink to its extruded diameter when heated. The tubing s