Insulators ← Knowledge Base Why would I want to have zinc sleeves added to the pins of my toughened glass bell suspension insulators? Why do some toughened glass bell suspension insulators have color bands applied to them? Is there a standard which dictates the use of color bands for toughened glass bell suspension insulators? Where are our toughened glass bell suspension insulators manufactured? Are the toughened glass bell suspension insulators subjected to any type of thermal testing? How do you calculate BIL for your Transmission insulators? What makes your Bonded SR insulator better? What does Quadri*Sil™ stand for? What is corona? What are your testing capabilities? What is the average life span of the Quadri*Sil™ insulators? What is the torque value for the bolts of the P250 and P300 bases? What is the proper orientation for corona rings? What do I need to know to select a transmission insulator? There are multiple terms in the catalog tables presenting data on various distances. What do each of these terms mean? Do you supply mounting hardware with Quadri*Sil line post insulators?