Porcelain Spool insulators 1)good quality 2)Factory direct price 3)professional ... requirements.4) Type: pin type,post type,disc suspension type,spool/shackle type,strain typea. Disc InsulatorsDisc Suspension Insulators for HV ... -1,54-2,54-3,54-4,54-5 e. Spool Insulators for ANSI & BS 5) Colour: gray,brown,white,blue ...