Cotter Pins (bag/50) 14 ga Cotter Clips are an economical and secure way to fasten the wire to line posts. Holes can be easily drilled in a G2 line post after the post has been installed in the ground by using a cordless drill and 3/16" drill bit. spread the clip to place around the wire, then push both legs of the clip together through the hole and bend the ends back around the post toward the fence wire. Do not wrap the cotter clips around the wire. These cotter pins are also perfect to use with fiberglass post.