Snug SWP insulator for wood posts. Heavier and tougher than others. Insulator rests on 3/4 In. nail surface. Won't tear or crack loose. Flexible base fits round or flat sided posts. Molded of high-density polyethylene with UV (ultra violet) inhibitors for all-weather durability. Extends wire 2-1/8 In. from post. Snap-fast. Quickly and easily installed with shingle nails. 25 per bag.