Here's a new item that Batson is carrying that is a heavy duty alternative to heat shrink that would work great for rail rods.

https://video.fsnc1-2.fna.fbcdn.net/...ef&oe=589BED50

Made in 12 and 18 inch length. Here's the details of the cold shrink tubing:

http://alpsforecast.com/products/shr...d-shrink-tube/