Usoro dum nke Johnson electric insulator n'ichepụta mmepụta

Usoro mmepụta nke nkwusioru poselin insulator na-eme ihe ọkụkụ gụnyere ọrụ nrụpụta ndị a:

Egweri → Ime ụrọ → Pugging → ịkpụzi → Ihicha → Glazing → Kilning → Nnwale → Ngwaahịa ikpeazụ