Fi-Shock IT2XY-FS Snap-On Extender T-Post Insulator, 2-Inch, Yellow
Insulators allow you to fasten electrified wire to the post without losing energy through the post.   The Fi-Shock Yellow Snap-On 2" Extender T-Post Insulator fits securely on standard (1.25 or 1.33) studded T-posts. It is fabricated as one molded piece, so it needs no hardware.   These yellow electric fence insulators are packed 25 per bag.