Ceramic/porcelain insulator base fitting`s material can be ductile cast iron, malleable cast iron, and low temperature ductile cast iron. And the thread have 3/4``-10, 5/8``-11+. 015`` ect according to client`s drawing.
And the tread will be checked strictly by special gauge. The base can be one hole, four hole. And will be tipped accroding to client`s requirments
Audited Supplier 
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