PI 21n Notched Terminal Insulator

For insulating low-tension fences at corner and end posts and around trees. Notch eliminates need to thread strand of cable or twine through insulator.

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369200 PI 21n Notched Terminal Insulator In Stock 0.08 $1.03

How to install a PI 21n Notched Terminal Insulator

Common Uses

  • Use with rope, twine, MaxiShock, and cable. Saves time and hassle by being able to slip the conductor through the notch.
  • Use for trees, ends, corners or curves of semi-permanent and temporary fences.

  • Glass filled nylon
  • 2.75" long x 1.25" wide
  • Packaged in bags of 25, but sold individually
How to Use

  1. From the closed hole, attach insulator to end or corner post or tree. Any type of material can be used (rope or wire).
  2. Through the notched set of holes, thread fence wire and terminate at ends, or continue on for corners.

If using this insulator for rope or MaxiShock, a P Spring (sold separately, see accessories tab above) can be tied directly to the insulator prior to fence wire being attached to P spring using rope or wire.

When the fence wire is pulled tight, this insulator will pull away from the post.


It is sometimes difficult to get large rope through the notch. To help this, just twist the rope backwards and it will slide in.

Listed below are recommended optional components or related items. Your particular situation may require alternative recommendations. Please call and talk to our consultants if there are any questions at 800-282-6631.
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Average Rating: 4 out of 5
Number of Reviews: 3 customers reviewed this product.

Write a Review

Date: November 25, 2014
Michael C from Louisiana
Would you recommend this product? Yes
This is a half baked design in my opinion. Good start, but needs work. The only reason I feel compelled enough to review it is they failed exactly how I expected them to.

It is difficult to explain but because of the way that the wire must go into the insulator (horizontal as shown in the picture) the part that attaches to the post is extremely awkward, at best.

You have two options, loop it through the given hole which is vertical which causes the insulator to twist, or you have to loop it through the horizontal open hole furthest away from the post. That can cause the insulator to flip down which can pop the wire out and in my cause caused a gate handle to pop out, releasing my goats.

I might recommend pairing these with zipties to hold them firmly in place.
Date: April 18, 2012
Joe H from SC
Would you recommend this product? Yes
Simple and last a long time in service. Never had a failure.
Date: May 25, 2010
Jackie G
Would you recommend this product? Yes
Great invention. Made stringing the fence so much quicker! I will use only these in the future (other than at rope gates). The regular insulator works best there.