Insulators allow you to fasten electrified wire to posts without losing energy through the post. Some electric fencing situations are unique, requiring their own special type of insulator. Our Red Snap'r® Tube Clamp Insulator is adjustable to fit all 1-5/8" to 1-3/4" diameter horizontal tubes. Unique ratchet lock prevents slippage. For use with poly wire, poly rope and steel or aluminum wire. Note: Not for use with poly tape or high tensile fencing. Red Snap'r® Insulators are made from only the highest grade, high density polyethylene, resulting in a rugged durable construction. They provide excellent insulating characteristics and are UV-protected to resist weathering, even under the harshes conditions. The models are designed for easy attachment to fence post or wire.