1. Tie Top Porcelain Line Post Insulators are designed for upright or angle mounting on a crossarm. They are rated from 25kV to 69kV in usual line voltage, and requiring a cantilever strength of 2800lb. For wood crossarm, long studs are supplied complete with large area flat washer ,square nut and lock nut. For steel crossarm,short studs are supplied with standard hex nuts and locknuts.

2.Conductor grooves are the wide Tie Top  ANSI standard type with head and neck designed for the use Wraplock or conventional tie wires.

3.Gray glaze is standard for this ANSI type tie top porcelain line post insulators,Brown glaze can be supplied on order.

4.The ANSI standard No. for these Tie top porcelain line post insulators are: 57-1,57-2,57-3,57-4,57-5, with S or L after the number  respectively represent short stud or long stud.For example : 57-1S means: short stud is supplied with 57-1 line post insulator.

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