Top Rail Lock Device - 1-3/8" Top Rail x 1-5/8" post-set of 4

This listing is for FOUR Top Rail Locking Devices for 1-3/8" top rail x 1-5/8" line post.  One per 20' is recommended. This Top Rail Locking Device keeps the top rail from rotating and can be used with Extend-A-Post and Extend-An-Arm products.  One pack of four covers approximately 100'.  Self-drilling screws are included.