Zareba Fi-Shock IT2XY-FS Snap-On Extender Insulator, Yellow

For fastening electrified wire to the post without losing energy through the post. Extender insulators extends wire 2 in or 5 in (depending on item) from post. Fits securely on standard (1.25 or 1.33) studded T-posts. No hardware is needed to put this insulator on a post.